So, first day is over and it was really interesting. Initially I wanted to do a little microorganism simulator but I overestimated my programming ability (thank goodness for that) and had to come up with something new. I spent several hours just during programming random motion. And it was even the easier part.
Second idea I get was space adventures, which goal was terraforming asteroid to tiny planet, but I had no idea what would the player did there.
Finally, my third idea was to create maze on circuit board which the ant had to go through without touching the electrical conductor. And I think it is pretty good. Programming is quite simple, so I can focus more on graphical aspects. For half a day I have programmed the base engine and created most of the graphics.