I just made a simple game and exported it in HTML5 !
It's in French but very simple : it's a Nim game. Every turn, players must remove 1, 2 or 3 matches from a 21-match pile. The player who takes the last match loses. There's a 2-player mode and an AI (which plays with the perfect strategy).
If you think it would be good as an example game I could make an English translation...
It works nice on Chrome, Firefox, and on my small Android phone (very laggy though, but since I based all animations on time and not on frames it isn't much of a problem)
EDIT : oh and by the way, I've made a small educational game. It's also in French but I'm sure you will understand everything : http://www.zoglu.net/trucs/maths/comparaisons/
EDIT #2 : also one of the things I looooove after building an application is looking at the mosaic files with all the graphical assets in a single image : http://www.zoglu.net/trucs/nim/files/jeux/nim/M0001.png
or even better : http://www.zoglu.net/trucs/BloXRoX/M0002.png