The toys we loved as children can now be worth huge sums if you were one of the few good (or strange) enough to keep them in their original box and in mint condition. Here's our top five collectible children's toys ever sold at auction.

5. Steiff bears

The original Steiff Type 55 PB would break all records should it ever surface

The teddy bear's name originates from president Theodore Roosevelt's famed hunting trip in 1902, on which he refused to shoot a bear cub that his men had beaten and tied to a tree. The incident soon became the topic of a political cartoon, which in turn inspired New York toymaker Morris Michtom to create "Teddy's Bear" - the world's first cuddly bear toy.

At approximately the same time in Germany, the Steiff company was already working on its own teddy bear, which was affectionately dubbed "Type 55 PB". Although they were certainly produced, none of these bears have ever been seen since, with rumours circulating that they were shipwrecked on their way to the US. One of these Type 55 PB bears would undoubtedly become the world's most expensive bear should it ever surface.

However, that title is already held by a Steiff bear. The company's millennium edition bears, of which only 41 were produced, were each individually dressed by a renowned designer. The Louis Vitton bear stands as the most expensive of the series, selling for $195,000 at a special auction on their release.

4.  Barbie dolls

The original 1959 Barbie was issued in both Brunette and Blonde

Barbie, or Barbara Millicent Roberts, has long been the glamorous favourite of little girls across the world. This love is often carried through to adulthood, with collectors investing thousands to regain that glimpse of their youth.

Original Barbie dolls, first released in 1959, in mint boxed condition sell for around $4,000 today. However, it is the limited edition Barbie dolls that command the highest prices at auction. In 2010, a Barbie designed by Australian Stefano Canturi sold for $302,500 in a charity auction at Christie's. No ordinary doll, Barbie wore a simple black party dress, which was subtly offset by a necklace studded with a one carat pink diamond surrounded by three carat white diamonds.

3.) G I Joe action figure

America's movable fighting man

One for the boys and the male equivalent of a Barbie (it's an action figure, not a doll!), G I Joe was the first of his kind ever created. Produced by Don Levine in 1964 for toy manufacturing giant Hasbro, the three hand-carved prototypes were originally named Rocky, Skip and Ace.

One of these prototypes (unfortunately, we don't know his name) sold for $200,000 at Heritage Auctions in 2003. It was bought by noted toy collector Stephen A Geppi to be housed in his Geppi's Entertainment Museum in Baltimore, Maryland.

2.  Monopoly

Fancy playing a game against Malcolm Forbes?

Remember those rainy Sunday afternoons, when a sibling would drag out the tired old Monopoly board, ready to take all your worldly possessions and destroy your property empire yet again? We do, perhaps a little too well…

Then imagine if that sibling was media mogul Malcolm Forbes, one-time owner of the world's first Monopoly set. First produced in 1933 on a circular board with handmade hotels, Forbes' classic board game sold for $146,500 at Sotheby's in 2010, as part of his renowned toy collection.

1. Titania's Palace doll's house

Sold for $256,500 in 1978

Sheer lavishness makes this one our number one. Taking 25 years to build, British author Sir Nevile Wilkinson finally finished this 18 room mansion in 1922, after filling it with tiny hand-carved mahogany furniture and around 3,000 miniature works of art.

It was sold at a Christie's sale in 1978 for an impressive $256,500, becoming the world's most expensive doll's house - a record that still stands today. Toy manufacturer Lego bought the stately house, displaying it at its Legoland attraction in Denmark for years, until it was removed in 2007.