I recently bought a pair of Vibram FiveFingers Sprint (pictured). They're minimal, lightweight shoes with "toes". They're designed to mimic barefoot walking as closely as possible, while protecting the feet from punctures and abrasion. The soles are thin, flexible and offer no padding whatsoever.
I've always been a barefoot walker, because I enjoy it and our feet evolved to be nude (or close to it). Besides feeling amazing, walking barefoot may allow the body to express better biomechanics. My feet have become tougher over time, but I still can't handle a rough trail barefoot.
When I first put the FiveFingers on, my initial thought was "these don't feel as much like being barefoot as I wish they did". Simply having something between your skin and the ground makes your feet much less sensitive. But I got used to them quickly, eventually using them for my parkour training.
I had a few converstions with my parkour instructor Rafe Kelley, during which I realized I had to re-teach myself how to walk and run correctly. Rafe is well-versed in natural human movement due to his background in MovNat, gymnastics, martial arts, strength training, parkour and anthropology. Modern shoes allow us to walk and run in a way that our bodies did not evolve to tolerate. The padding in shoes allows us to take large steps, in which we overshoot our center of gravity and contact the ground in a jarring manner. It also allows us to strike with our heels when we run, which is not comfortable when you're barefoot.
I took the FiveFingers on a 13-mile hike in the Alpine Lakes wilderness with a few friends last weekend. The Pacific Northwest has to be one of the most beautiful places in the world. I was expecting to use the shoes for a few miles and then swap them for my lightweight hiking shoes (Inov8 Flyroc trail runners). The beginning of the trail was really rocky and I thought I was going to have to take them off in the first few hundred yards. Surprisingly, my feet adapted, and although the trail stayed rocky, it became fairly comfortable by the time we had walked a mile.
I found myself thinking about Rafe's advice, and taking smaller steps that strike closer to my center of gravity. Although my strides were shorter, I had no trouble keeping up, and in fact going up the hills was remarkably easy. We gained 3,000 feet of elevation but I never got winded. I had to pay close attention to foot placement, which kept me from looking around much but was actually kind of fun.
After a few miles, I switched to my hiking shoes, with the idea that I should switch before my feet really started to hurt, rather than after. I immediately noticed that going up hills was harder, especially on my calves. My feet felt more cumbersome as well.
Here's me foraging for mushrooms on the trail. This is Laetiporus sulphureus, also known as "chicken of the woods". It's widely eaten in this area. However, my mushroom guide All That the Rain Primises, and More, had this to say about it:
"If you eat and enjoy this moushroom, always cook it thoroughly and do not serve it to lawyers, landlords, employers, policemen, pit bull owners, or others whose good will you cherish!"
I didn't take my chances. If you're going to pick wild mushrooms, make sure you know what you're doing and carry a regional identification guide. "I recognize them from China/Russia/Europe" kills several people a year in the Pacific Northwest. If you're experienced, this area is a mushroom bonanza. I can't set foot outside without stepping on a king bolete (porcini, cep) in the fall.
I ended up switching back to the FiveFingers for the majority of the hike, about 9 miles of it. The soles of my feet were a bit sore by the end (due to stepping on sharp rocks for miles), but my joints and muscles felt remarkably good! I had no joint pain or muscle tightness. I also felt pretty energetic. This was a big surprise, since I haven't done much hiking this year. The next day, my calves were sore, but that was it.
All in all, I really like the FiveFingers. I can wear them in places that require shoes, yet remain nearly barefoot. One potential drawback is the price-to-durability ratio. They cost me $80 and I don't expect them to last a year [Update 2013-- they are surprisingly durable]. That being said, I'm putting a beating on them. Parkour training destroys shoes. The rubber seems to be excellent quality (which you'd expect from Vibram), but it's thin and it has cuts in it for flexibility and grip, which will lower its lifespan. The upper is simply a piece of stretchy fabric that tears easily. I'm willing to deal with the durability issues because the advantages outweigh them [update- several FiveFingers wearers have commented that they actually last a surprisingly long time. See comments].