Remember when "The Pump" sneakers came out and kids were getting killed over them? Remember those sneaker ads where basketball players implied that if you wore their sneakers you'd be dunking on your friends in no time? Then, about $100 later, you had the shoes and learned that you were just as terribly unathletic with them as you were before. But at least your feet looked cool while you were getting your ass handed to you on the court.

Well, amazingly, after all my travels in the world of fitness and having encountered every possible gimmick, I've finally come across shoes that DO make a difference. In fact, they work right away. They're called Vibram Five Fingers.
The design behind them is simple--make a shoe that's as close to being barefoot as possible. In a perfect world with 75-degree weather and no concrete sidewalks littered with gum, nails, and broken glass, we'd all be barefoot. Going barefoot strengthens your feet and teaches them to react to the ground properly. Foot, ankle, knee, and lower-back pain disappears as each link in your chain learns to better stabilize itself. In time, you're able to run more efficiently and lift more weight. Your whole body becomes more athletic.
Vibrams replicate being barefoot very nicely, providing just enough of a rubber sole to keep your feet safe. Your toes are free to wiggle and your feet can grip the ground. There is no need for arch support because your arches will learn to support the feet by themselves. The only thing to be wary of is that because Vibrams are such a departure from the typical athletic shoe, you need a few weeks to get used to them. Don't try to run five miles on your first day or your feet will be too beat up to run for a long time after.
On a personal note, I've been wearing a pair for about a month and I've found that my deadlift has gone up considerably. I would credit it mainly to the shoes allowing my feet to be so low to the ground, which allows for a mechanical advantage in lifting the weight (less distance to overcome and a firmer base).
Finally, a shoe worth killing for.*
*Men's Fitness does not endorse or condone the use of murder to acquire Vibram Five Fingers shoes.