I started concentrating on artificials 7 years ago. Was a live bait fisherman forever. Since that time i've discovered SO many productive lures for different conditions.
I would have to say that the most versatile lure and most productive lure has been the Senko.
Texas-rigged plastic worms have traditionally been the most successful lures for bass fishermen for years. The Senko, I believe, takes this approach to ne heights in it's simplicity to work for both the professional angler and the novice angler.
And I also LOVE the Rapala Husky Jerk. Sure, the X-Raps are the new craze, but the Husky Jerk has landed me several species of fish on many waters.