If you think the toys and other collectables that come free with fast-food meals, breakfast cereals and other products are useless pieces of junk worth next to nothing, you may need to think again. Here is a selection of free toys and memorabilia that fetch surprisingly high prices.

UK bank NatWest scored a major marketing coup in the early 1980s with the launch of its range of ceramic piggy banks. Kids up and down the land badgered their parents to open an account just so they could get their hands on one or more of the piggies. The first and most common of the five collectables, Baby Woody was gifted to young investors who deposited at least five pounds. The piglet sells for up to $25 (£20) these days.

Dubbed 'premiums', cereal freebies from way back when can fetch impressive prices. This Adventures of Toucan Sam comic was given away as a mail-in Froot Loops promo by Kellogg's in the US back in 1994. Today, a mint-condition copy can easily make up to $55 (£45) on eBay or similar auction sites.

Another 1990s mail-in promo, this set of four cereal bowls featuring the Teenage Mutant Ninja Turtles was dished out to customers who had amassed a number of tokens contained within the official TMNT cereal, which was produced by Ralston. A set recently sold for $60 (£50) on eBay, not bad at all for a freebie offer.

McDonald's Happy Meal toys may seem like throwaway pieces of plastic destined to end up on landfill, but the most sought-after specimens command surprisingly high prices. So don't throw them away if you haven't yet. A set of 1980s or 1990s Mr. Potato Head Kids toys for instance is worth up to $70 (£58) at the current time.

For a limited period in 1988 specially marked boxes of Post Pebbles Cereals in the US came with sachets of The Flintstones-themed Kool-Aid. Two flavours were available, Yabba-Dabba-Doo Berry, which tasted of strawberry, and Bedrock Orange. These days, a sachet sells for up to $70 (£58).

Burger King has given away some nifty playthings over the years. In 2000 the fast-food chain ran a Dragon Ball Z promo consisting of seven toys, stands and cards. Today, a full set fetches up to $75 (£62).

Tying in with the release of the Nintendo Super Mario Bros. 3 game in 1990 in North America, McDonald's issued a set of four Happy Meal toys featuring the iconic video game plumber as well as Luigi, Little Goomba and Koopa Paratroopa. Nowadays, the full set is valued at up to $80 (£65), with individual toys selling for $20 (£16) each.

Launched in 1958, Kellogg's Sugar Smacks would often come bearing gifts. In 1966 Kellogg's UK embarked on a memorable ad campaign and giveaway of themed toys featuring models inspired by classic British sci-fi show Thunderbirds. These toys are worth up to $80 (£65) a-piece at the current time.

Before Captain Jack Sparrow there was barefoot pirate Jean LaFoote. The fictional buccaneer has featured on packets of Quaker Cap'n Crunch since its launch in 1963. This mail-in premium coin bank was given away as a freebie in 1975 in the US and will net you up to $100 (£82).

Distributed by the cult West Coast fast-food chain at promotional events, the In-N-Out Burger coin is prized by devotees of the restaurants. Each coin entitles the bearer to a free burger but if you're privileged enough to own one, forget about redeeming it. Collectors will pay up to $100 (£82) for the rarer coins, the equivalent of 29 Double-Double Burgers.

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Back to McDonald's Happy Meal freebies. If you managed to collect the full set of Disney 102 Dalmatians toys back in 2000, you'll be pleased to discover your complimentary collection of cute plastic pooches is worth up to $115 (£95). 

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Collectors of cereal box toys hold these monster freebies in especially high esteem. Available in the US in boxes of Ralston Freakies cereal from 1972 to 1976, the colourful beasts came in seven varieties. A full set sells for up to $120 (£99) these days.

Collectors are also crazy about R&L Cereals' Crater Critter toys. Originally issued in Australia in 1968, they are considered a must-have for cereal toy aficionados. Kingly Critter is the rarest of the bunch – it sells for hundreds of dollars – but even the less scarce Kindly Critter (pictured) and similar toys go for up to $120 (£99).

Many a Baby Boomer in the US collected the baseball cards that were contained in Post Cereals' packets during the early 1960s. Value-wise, this Sandy Koufax #109 card sells for up to $150 (£124) these days, while a full set of 200 from 1962 can realise up to $3,000 (£2.5k).

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In 2000 McDonald's marked the 50th anniversary of the Peanuts comic strip by issuing a set of Snoopy Happy Meal toys. A full set will garner you a very respectable $180 (£148). Incidentally Wendy's gave away Snoopy toys in 1998 but a full set is worth a fraction of the price of the McDonald's offering.

If you or your children collected Burger King Kids Meal toys during the 2000s, have a hunt around for the Viva Piñata Party Animals toys. Released in 2007 when the computer game featuring the animals came out, they are worth big bucks, particularly the rarer Macaraccoon, one of which recently realised $200 (£165) on eBay.

UK bank NatWest revived its 1980s Pig promo in 1999 to promote a personal savings bond, adding a new piggie called Cousin Wesley to the family. The financial product called for a minimum investment of $1,200 (£1k). As only 5,000 were made, this coin bank is relatively rare and commands prices of up to $243 (£200) at auction.

In 1985 Burger King rolled out an extra-special four-week promo for Masters of the Universe fans consisting of various themed He-Man cups. Here's hoping you have a few stashed away somewhere – a set of 15 sold on eBay in June for $250 (£206).

To coincide with the Inspector Gadget live-action movie in 1999, McDonald's offered a set of toys featuring the hapless cyborg detective. Fast-forward to 2019 and a full set of these freebie Happy Meal toys sells for $300 (£248).

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If you have a collection of IHOP Pancakes toys gathering dust somewhere, you could be in for a mini windfall. Collectors pay top dollar for these playthings with a set of 23 recently selling for $305 (£252) on eBay.

Australian supermarket chain Woolworths has sparked a major craze Down Under with its Lion King Ooshie promo. The rarer toys among the range of 24 have fetched silly prices on eBay. By way of example a blue glitter Spirit Mufasa toy recently went for $350 (£289).

McDonald's has given away various Minions toys over the years to tie in with the release of the four Despicable Me movies. If you're lucky enough to own a complete set, you could be sitting on up to a cool $400 (£331).

These adorable mini Beanie Babies from 2000 are among the most valuable Happy Meal toys, which figures given the full-sized Beanie Babies were such a major craze around the time, and still count legions of nostalgic fans. Today, a full set will fetch up to $450 (£372).

Back to those highly desirable NatWest piggies. In 2006 Natwest gave away a limited number of gold coin banks to kids who participated in a treasure hunt competition. One of the scarcest of the bunch is Maxwell. This little piggy is worth up to $600 (£500) these days.

The rarest and most desirable piggy of them all however is Sir Nathaniel Lombard. The ceramic hog was produced by Wade for NatWest Lombard bank and handed out in very limited numbers during the mid 1990s. Nowadays, the titled pig sells for some $800 (£650).

Like Beanie Babies, Furby toys were a massive fad in the late 1990s. McDonald's got in on the action, albeit a tad late, in 2000 with the launch of its Happy Meal range of clippable Furbies. A full set of 12 is worth up to $900 (£745) at the current time.

In 2013 Toys R Us ran a legendary Star Wars promo at its flagship Times Square store giving away 1,000 NY I Heart Yoda Lego figures to customers who purchased X-Wing playsets. Sadly, the New York City store closed down for good in 2015. These days, collectors will shell out up to $1,000 (£827) to get hold of the branded Yoda figure.

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Wonder Bread delighted Masters of the Universe fans back in 1983 when it launched a mail-in promo offering the so-called Wun-Dar He-Man toy. Today these He-Man figures sell for huge sums online, going for anything up to $1,000 (£827) in fact.

In 2002 McDonald's celebrated Disney's centenary with a range of 50 Happy Meal toys. A full set of the plastic playthings, which feature characters from Mickey Mouse to Princess Aurora, recently went for $2,500 (£2.1k) on eBay, making it the most valuable Happy Meal set of them all.

With the Woolworths Lion King Ooshie promo reaching fever pitch, the rarest toy has fetched jaw-dropping prices on eBay. A limited edition of just 100, Furry Simba is worth a fortune. One sold recently for $3,500 (£2.9k), while another is said to have fetched $67,700 (£56k), though that particular sale hasn't been confirmed.

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