I got one of these in black awhile back:
http://cgi.ebay.com/3-Day-ASSAULT-PA...3%3A1|294%3A50
has hip and chest support, a hydration pouch against the back that will fit a larger laptop, and pretty easy to organize. Comfortable to ride with on a bike, even loaded heavily thanks to thick straps and the supporting straps. I pretty much carry it everywhere.