Dubbed 'premiums', cereal freebies from way back when can fetch impressive prices. Froot Loops regularly had freebies in its colourful boxes, such as the mystery action toy edition pictured. One of the most valuable of the bunch was the mail-in Adventures of Toucan Sam comic given away 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, these cereal bowls featuring the Teenage Mutant Ninja Turtles came as part of a set of four and were dished out to customers who had amassed a number of tokens contained within the official TMNT cereal, which was produced by Ralston. A full set recently sold for $60 (£49) on eBay, which isn't bad at all for a couple of green plastic bowls.
The highlight of a Kinder Surprise egg is usually the chocolate rather than the plastic toy it contains, and for the most part the little toys really aren't worth much individually. But there are collectors willing to buy joblots of the surprises however, and if you've got a drawer full of them stashed away somewhere, they could be worth selling. In April, a collection of pre-owned Kinder Surprise toys went for £50 ($62) on eBay.
McDonald's Happy Meal toys seem like throwaway pieces of plastic destined to end up in landfill, and the fast-food giant has pledged to ban the toys for environmental reasons. That said, the most sought-after toys still command surprisingly high prices, so don't throw them away if you haven't yet. A complete set of 1980s or 1990s Mr. Potato Head kids' toys for instance is worth up to $70 (£57) at the current time.
Burger King announced that it would no longer be giving away plastic toys in September 2019, but it has given away some fun 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 (£61).
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 cereal 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.
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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-Doubles.
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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).
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 (bottom right) is the rarest of the bunch – it sells for hundreds of dollars – but even the less scarce Kindly Critter (top right) and other toys in the collection can go for up to $120 (£99).
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 even if you have a full collection it's only worth a fraction of the price of the McDonald's offering.
To coincide with the release of the Inspector Gadget live-action movie in 1999, McDonald's offered a set of toys featuring the hapless cyborg detective. Fans of the film had to collect up the different body parts in their Happy Meals before they could assemble their own action figure. Fast-forward to 2019 and a complete Inspector Gadget sold for $300 (£248).
Australian supermarket chain Woolworths sparked a major hype Down Under with its Lion King Ooshie promo. The rarer toys among the range of 24 have achieved high prices on eBay, for example a blue glitter Spirit Mufasa toy recently sold 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 of the unintelligable yellow characters, they could earn you up to $400 (£331).
These adorable mini Beanie Babies from 2000 are among the most valuable Happy Meal toys, which is unsurprising given that full-sized Beanie Babies were such a major craze at the time of their release. The squishy toys still count legions of nostalgic fans today and a full set of the mini versions can sell for up to $450 (£372).
Back to those highly desirable NatWest money banks. In 2006 Natwest gave away a limited number of gold coin banks to kids who participated in a treasure hunt competition and one of the scarcest of the bunch is Maxwell. You might want to take this little piggy to a market – an online marketplace that is – as he is worth up to $600 (£480) these days.
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.
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).
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 sold for a whopping $67,700 (£56k), although that particular sale hasn't been confirmed.
Now read: Most expensive toys sold at auction