Gray Lines was a project that I worked on in 2007-2008 while I was in high school, before I had any real formal training in programming. After letting the completed game sit in my computer for around a year I decided to submit it to Newgrounds in September 2009, and it made the front page there.
The game is a puzzle platformer where the player moves with WASD, and can draw lines with the mouse. These lines can be used as platforms by the player, or to hold down switches which open doors in the environment.
Since it is a flash game it is embedded and can be played above.