Vibram Five Fingers + TRX = Winner!

These shoes are literally like being in barefeet but with a functional, protective carapace. Their sticky and flexible soles make them awesome for yoga with or without a mat (one less thing to pack when traveling!) and even better for building functional foot strength while using the TRX. I TRX barefoot whenever possible, but the sticky Five Fingers are great for slick surfaces and are superior to barefeet for movements that require balancing on the heels.

Absolute homerun combination.