Inspired by Christopher McDougall's Born to Run, I've been running barefoot for short distances--usually about 1/2 mile, as terrain and temperature allow. I've gotten a few odd looks, but even these short runs have had a positive effect on my shod running. My base mileage continues to increase as my long runs get longer--and, more importantly, I'm still injury-free!
I don't attribute this solely (no pun intended) to my barefoot jaunts, except insofar as they've been forcing me into running more lightly: with a faster tempo, shorter strides, and a footstrike that's become less heel and more midfoot. That's essentially the running style suggested by both Danny Dreyer's Chi Running and Nicholas Romanov's Pose Technique, but I haven't investigated them in detail yet. I'm still experimenting with various Injinji toe socks, and the Vibram Five Fingers (VFF) shoes are probably next on my horizon.
Because I tend to over-research everything, I've been devouring nearly every barefooting resource that I could find. Here are some of them:
"Barefoot running" (Wikipedia)
"You Walk Wrong" (NY Magazine) identifies "the shoe paradox:"
We've come to believe that shoes, not bare feet, are natural and comfortable, when in fact wearing shoes simply creates the need for wearing shoes. [...] Shoes are bad. I don't just mean stiletto heels, or cowboy boots, or tottering espadrilles, or any of the other fairly obvious foot-torture devices into which we wincingly jam our feet. I mean all shoes. Shoes hurt your feet. They change how you walk.
The paper "Shod vs. Unshod: The Emergence of Forefoot Pathology in Modern Humans?" concludes:
The results presented here suggest that the unshod lifestyle of the pre-pastoral group was associated with a lower frequency of osteological modification. The influence of modern lifestyle including the use of footwear, appears to have some significant negative effect on foot function, potentially resulting in an increase in pathological changes. (p. 212)
Tim Ferriss posts some disturbing photos of shoe-altered feet
"Wiggling Their Toes at the Shoe Giants" (NYT) discusses the shoe industry's "move toward minimalism"
Clynton proclaims at Running Quest that barefoot running is "Not Just for Bums and Hippies Anymore" and also includes a great list of minimalist shoes that are not quite as extreme as the VFFs.
"Lose Your Shoes: Is Barefoot Better?" (Neuroanthropology)