I've got a pair of Freefloats for sale. Only used them once at the last party I hosted a few years ago. Basically they are inflatable cushions that are made to sit under turntables so that they aren't affected by bass vibrations and people stomping in front of the stage. I find they make the bass "punchier", I suppose from the needles having less outside vibrations to deal with.
Good especially for smaller rooms where there's lots of bass and people dancing right in front of the stage.
I find them great, except turntablists aren't huge fans. Then again, if you're doing any crazy scratching or beat juggling, you're probably not playing the type of music that makes people jump up and down right in front of you like some douchebag that doesn't get that he's skipping the track.
$25
PM me or reply here if interested