Yes, my 5 year old has loved playing with Tux Paint since he was 2 (and his younger sister is just as keen on it). He needed a bit of help with the mouse, at first, but now has no problems at all. He'd be playing with it all day, if I let him...

I've had this happen with friends' Yahoo accounts (also offering Chinese electronics), so it isn't exclusively a Hotmail problem.

On the 'scary crypt' level (sorry, can't remember its real name), of Donkey Kong 64, you can jump into the wall torches at the right angle and go straight through a wall. There's not much to see, but still slightly satisfying. In Superman Shadow of Apokolips on PS2 there's a few walls on the reactor level (by the big glowing-ball thingy), that you can fly through... but there really is no point at all (I found them too late for them to be fixed before the game shipped).