Here is a thing! You can use it to make beepy noises, and you may notice that it fills your clipboard with chunks of code. That code is what I use to then play the beepy noises in GameSketch, so yeah, it's a tool for me that I've published here even though you can't really use it for anything. Um... sorry? Anyhow it's pretty fun, and if you're interested in such things it'll give you a good idea of how the GameSketch synthesizer works.
The first four sliders set pitch. The first two give the octave and note (offset from the middle) of the start of the beep, and the second two give the octave and note of the end.
The next two sliders set the initial and final volume. Full volume is actually half way up, with full slider height giving a nice overdrive effect.
The next two are a different kind of distortion, again as the start and end of the beep.
The final slider is the beep length.
The tabs down the bottom select individual beeps that are played back in sequence. Combining these together can create more complex sounds and short melodies.