Got a set of Automoblox Minis for my daughter for her 4th Birthday and she loves them! She's been playing with them for days. We got her a set of three so she can pull 'em all apart and make new stuff. Lots of combinations and you can get more sets or individual cars to make even more variations. The set even came with an extra set of wheels and tires and the rubber tires are even swapable. One word of caution - if your kid is the kind that likes to put stuff in thier mouth, the wheels for the mini versions are really small so it might not be a good toy for them, or if you have babies around.
