1) you should try buying the "regular" effects and really get into them. A good delay pedal (DD-3) can get you some weird sounds. Ever try twisting the delay time knob while something is delaying?

2) There is this thing called a "ring modulator". I beleive it is something in terms of a trem like effect but much harder and weirded to use. I have never seen one and to my knowledge do not ever remember hearing one.

3) Electro Harmonix has some effects that aren't like the regulars made by BOSS or MXR. Check out their website.

4) You could try and find a "theremin". It gives an extremely heavy reverb like sound. Check out Led Zep's "Whole lotta love". Or download some live Zep stuff and you might be lucky and find a song where Jimmy uses it.