I started a thread just like this two years ago after my Italy vacation. I wore a travel bag that I bought from AAA for a couple of weeks after but gave it up as it was just too big for carrying my wallet, iPod, earphones, PDA and keys. It's perfect if carrying more stuff like a camera, passport, travel book, food and water though.
Here's one that's not gay but super geeky.
http://www.eholster.com/eholsters1.html
Let us know what you end up getting. I like this but it costs way too much. I think I'll try a military surplus store like JYL suggested.
http://www.ebags.com/maxpedition/jumbo_153_versipack/product_detail/index.cfm?modelid=103244