Ken's Street Fighter 4 strategy guide here on EventHubs.com recently underwent several heavy revisions.Ken's Kara Throw is really good. It extends his throwing range considerably, and it helps keep your opponent guessing whether to counter the throw or block when you're close in.
To do it, you press towards your opponent and Medium Kick and immediately press Light Punch and Kick to throw. To most people it would appear as you're hitting all three buttons at the same time, but in reality the throw command comes out right after the Medium Kick, like it's part of the motion.
This results in Ken quickly stepping forward and then throwing, greatly extending his normal throw range.
This is helpful because you can cross your opponent up with Medium Kick, do two Crouching Light Punches, if you've hit you can go into a combo, if not you can do a Kara throw.
Until the other player learns to counter, you'll either throw them or land a big combo when you're able to cross them up with this strategy, guaranteeing some damage and much frustration.