Very Short List recommends a vital new time-waster.

“Eight years ago on SNL, [Christopher] Walken played a producer tasked with pushing ‘more cowbell’ onto Blue Oyster Cult’s already-anthemic ‘(Don’t Fear) The Reaper’. . . . Walken’s skit … inspire[d] More Cowbell — an absurdly wonderful Web app that turns any MP3 into a miniature disco inferno.”