Originally Posted by
TechMouse
Another idea is to experiment with different types of synthesis.
Subtractive synths are great, but there's a wealth of other stuff out there. I've had loads of fun messing around with FM synthesis, additive synthesis, and vector / wavetable synthesis.
There are loads of free VST plugins kicking around the net, and some of them offer very unique sound modelling engines.
Or if you get really bored, sit down and write your own... I ended up witing a square wave synth a few years back, for my dissertation. Learnt a hell of a lot about how everything works in the process.