http://www.entertonement.com/clips/g...red-warp-speed

Too late, vtecbratt. Randy Marsh already discovered warp drive.

"Stan and Randy Marsh not only broke a speed record, but actually appeared to have bent time and space and discovered warp speed."

Nothing happened to their world so I doubt anything could happen in our own reality. Only thing that I can think of that might happen is something simlier(but in another level of hardcore, gangsterness) to a sonic boom, but in this case it'd probably be some intense shockwave that could possibly pull matter in the direction of the machine that would be travling at warp speed. Nothing like a black hole since nothing in the universe besides supernoves can create 'em.