Most impressive thing...
I wrote a CSS capable web browser... (seriously... although it was extremely unstable and also took the best part of the day to render a large page... One day I'll dig it out again and fix the memory allocation so it doesn't take quite a long and then optimise the code)
It had plenty of missing features too..
No text selection,
No file input type,
Nothing apart from base rendering in fact.. although that wasn't 100% accurate either... But it DID render the sourceforge main page after 2 days.. lol