Our daughter really likes the movie The Last Mimzy. Of course, it is because of Mimzy. In the move, Mimzy is what appears to be a stuffed rabbit but turns out to be more than that. The Tonner Doll Company came out with a replica of Mimzy earlier this year and it was so popular it sold out (I think the Mimzy frenzie really hit when the DVD came out). You can buy them at e-bay, of course, but you'll have to bid a chunk of money to get it ($100 plus) when the ones available were originally $24.95 (there was a more deluxe version available for $59.95 or so).
New Line, the company that distributed the movie, made available a new talking Mimzy in a limited quantity of 2,000 just yesterday for the price of $29.95 (originally - they increased the price to $36.95 today). Despite there still being some available, these talking Mimzys are already showing up at e-bay for as much as $229.00 (Buy-it-Now price). If anyone bids on one of these Mimzys before the retail supply of 2000 is exhausted, they're nuts! If you want one go to New Line Shop before they run out but don't go to e-bay and pay a ridiculous price.
With e-bay there seems to be a trend. I think professional e-bayers are buying certain popular products to a point they are almost not available at your standard retail outlet (either brick and mortar or online). Our oldest son wanted a Bumblebee transformer based on the one recently seen on the Transformer movie. You couldn't find them anywhere except on e-bay. After some diligent effort on our part we located both versions (the older camaro model and the new one) at local stores right after being stocked. In both cases we got the last of each and ran into others trying to get the same ones.
I have purchased one toy on e-bay for more than standard retail once. It was a Jessie doll from Toy Story 2. We never saw them in stores and we really wanted to get it for our daughter because she was always playing with her brother's Woody doll. I did not, however, pay an exorbitant amount for it nor would I for any toy.
I will be watching this gift giving season to see what happens with these short supply high demand toys to see what prices are paid. I wonder if supplies will kick up for the transformers but thus far most retail outlets have had few of them (Wal-mart has been the worse) though Target and Toys 'R Us have had more in stock (though Toys 'R Us had been without them here locally for two weeks after they ran an ad advertising them - at least the $9.99 versions). Most likely procrastinators will pay - either in price or in a disappointed child.
Oh, and for those shopping on e-bay, check around before bidding.