For a quick HTML5 contest with fellow webdesigners, I created this clock with HTML5 and the Canvas.
You can change the color and style by clicking on the canvas.

Here you can see it in action

Other contestants:

• http://martijndegraaf.com/klok/iphone.html
• http://brianhokke.nl/html5/clock.html

Inspirated by this link, i wondered if i could create a mockup for such game with HTML5 canvas in 15 minutes, during my lunch break.
And so it came to pass, and 15 minutes later i had some sort of platformer with serious gravitation/collision issues.

nevertheless it was a good exercise: the result (arrow keys to move/jump)