My mission was to make a game with music in it and it took a lot more time that anticipated. The game became a 2.5D demake of Portal which actually became quite fun to play but the simulation is bit buggy on some systems.
The synth in the game is a 4-channel beauty with sine, square and noise oscillators. The only effect other than track volume is a delay loop for each channel. I recommend using headphones to hear the base frequencies. All in all I'm very satisfied with the end result. Both the music and the game is great.
You can play the game over at Java4k.com and the tracker can be found at https://bitbucket.org/bysse/tinysynth.
Don't forget to register a user and vote for your favorites!