ive seen loads, fur spring covers, traditional taped designs, theres a guy who has mounted lights on his.
theres an image in the gallery of someone who has rubber spikes.
easy ones to do that look good are tape, and i was thinking that if you get some meshed fabric thats light and tie it to the top of the springs at should float around nice when your bouncing.
im currently tossing round adding lights to my tyre mod, but they way i wanna do it may be a bit of an arse