I've resurrected my Nibbles clone from the spring and am getting the engine ready to be put into a full game. This is going to be called Snake Lab, and will feature a series of "experiments" (sound familiar?) with you as the snake. In addition to getting through the approximately 20 planned puzzle levels, there's going to be a sandbox mode and multiplayer.
Here's a couple videos:
The one below was made before the one above, and therefore lacks the features described in it.
Another screenshot:
And the current state in demo form: 
www.xerol.org
www.google.co.za