Despite my putative high level of net.geek.cred, I'd never heard of "Rickrolling" until the last day of March. LJ used a blog they set up to Rickroll their users as an April Fools Day joke; I went on to use their blog and Rickrolled a few folks myself. So Rickroll on with your bad selves! What are you waiting for? [P.S.: If you need to hide your attempts to Rickroll -- well, that's easily enough done. :) ]
Edit: This is absolutely hilarious.