Back during the time I worked with Flash a lot, I worked on copious amounts of unfinished game engines and gadgets. I did submit a few "finished" ones to Newgrounds:

Flee! - School project
Candy Man - Made an engine for pushing balls around and threw together a quick game around it. In hindsight it didn't turn out all that well...
Xmas Games Collection - Made one of the games ("Santa's Little Sorter") for this collection. My brother made the graphics.

There are a few other interactive thingies on there but they aren't really games, so.