That's an interesting idea... I don't have any tips for making this into a game (I'm not too good with original ideas ), but it certainly looks like it has a lot of potential.

If it helps, I think the faster mode looks better for a game. Maybe acceleration?

By the way, how do you decide which direction to turn in? Do you test the two sides when there's a collision and see if there's an opening on one?

Here's an idea for a game: Have the user draw lines as the snake is moving so it avoids death traps to reach a goal. The snake moves faster every round.

You could actually create levels where the snake has to get from the start point to an exit point. Along the way you can have enemies that kill upon touch, traps, (spikes, holes, doors that can close on you and smush you as you're trying to pass through them, flame throwers that toggle on/off) and power-ups that influnce behavior (speed up, slow down, reverse, extra lives). You could add objects in too if you liked; IE- buttons that trigger certain things like filling in a hole, making a "ramp" object appear to let you pass over a gap (more than one hole tile), or even open a door. Abuse objects and power ups in order to navigate levels from start to exit (IE using a speed up to get through a door that would otherwise smush and kill you. )

Any progress? This seems to be one of those little programs that begs for an idea to make it into a really creative game.

Woa, this is pretty neat!
I really need to try grammer for once

Hmm, I was thinking of doing that with using 2x2 grids so that it could follow "ramps" and whatnot.