I bought a pair of New Balance MT101's today. Their original purpose is trail running, but they work well for hiking and generally traveling. Less than eight ounces per shoe, relatively flat heel, thin sole; they're as minimalist as you can get with a conventional shoe. Probably too sportswear for a finer restaurant or club, but you got to compromise somewhere.
I'm using them for an upcoming adventure trip to Belize, and depending on their performance there I'm hoping they'll become the only pair of shoes I'll travel with (plus a pair of huarache sandals, I always need some kind of backup).