Mayhem is obsessed with Thomas the Tank Engine. OBSESSED. Not a day goes by where the Take Along trains are not played with. Nearly every day he requests I set up a track for him, each day having different requirements - one day a curvey track, the next with bridges, the next a 'big big track'. We have, depending on the stock at the libraries on any given week, 8-12 Thomas videos in the house & we watch about one of them a day at quiet time. I think that he has made 4 non-Thomas video requests since the first of the year - Over the Hedge, Cars (a former obsession), Madagascar and Barnyard.
It does make him easy to shop for on holidays & birthdays. I send my family an updated list of movies we own and trains we do not and they have no problem finding him something. He's getting Max & Monty and a new DVD in his Easter basket from my folks. At around $5 a train the Take Alongs make easy rewards for the chore chart, which explains why we have so many....
He's had other obsessions, Cars and Bob the Builder. Bob had no accessories but we borrowed a lot of videos from the library. Cars has one movie but lots of accessories, and we own most of the die cast cars (another cheap & easy gift for both boys). The Thomas seems to be the most lasting. We got our first Take Alongs about 2 years ago and there has never been more than a week or so when they are not n play. Those weeks tend to be in the summer. Thomas rules the winter.
I've managed to do a layout a month about it, inspired by Sweet Shoppe challenges