Vibrapods, and yes, I did. I put them under my old Jolida 202a. The feet on that thing sucked, though, so YMMV with better components.
I have been meaning to try some spikes on my current amp and pre... But haven't gotten around to it. I'm starting to think the spike idea is better than the vibrapod idea. Space is tight in the armoire they're in, tho... So I need to find some low-profile isolation devices. Any suggestions?
FWIW my new Moon Eclipse LE came with some sick spikes. I don't know if they make a difference, as I haven't tried with 'em off... But they sure look great.