I use the Direxion 3X ETFs, particularly FAS and FAZ, which move anywhere from 10% to 30% daily. I've seen them move over 40% in a single day a few times. Also good are TNA and TZA. Check out the Direxion site for the complete list of these 3X ETFs. Just don't tell Jim Cramer or he'll probably put a contract out on you, judging by how he rails on these things.