Reddit reviews Lumisource LS-MIR MADNESS Energy Saving Mirror Disco Ball Strobe

I agree on the mirror balls. Mirror balls are classy whereas a lot of the effects I see these days strike me as rather tacky or, if you are six years old, awesome. In the US you can get 8" mirror balls shipped for less than $10. Of course then you need some way to hang, rotate and illuminate them so there is the added cost of the motor mounts, lights and dilemma of how/where to hang them. Depending on how crafty/cheap you are you might possibly arrange something with multiple 8"-10" mirror balls, some clothesline and some borrowed LED bicycle headlights. A simpler solution might be multiple tabletop mirror balls: http://www.amazon.com/Lumisource-LS-MIR-MADNESS-Energy-Saving/dp/B0045CXY3E/ref=pd_sbs_indust_1

Also, consider a cheap fog machine: http://www.amazon.com/Eliminator-Lighting-Machines-EF-400-Machine/dp/B0006M59M6
Fog machines turn cheap lighting effects into pretty cool lighting effects.

FYI, virtually every effect made by American DJ and Chauvet have somebody demonstrating it on Youtube.