This is basically an urban, on-campus stylewhen I was in college, lo, those many years ago, I hauled around an ancient Gerry daypack and never really put it "on." So savvy marketing people picked up on thisin fact, I believe I was their inspirationand started designing easy-on, easy-off one-strap packs.
The other model, of course, is the courier bag, the quintessential one-strap pack, and a useful one at that. Eagle Creek's Runway ES ($40) is a slightly spiffed-up version of such a packit's on or off your back in a second, holds your laptop or other around-town necessities, and is made of tough Cordura nylon. The other sure-fire brand in this realm is Timbuk2, a staple of grungy bike messengers and road warriors everywhere. Try its popular ballistic-nylon Laptop Messenger ($90; www.timbuk2.com) or customize your own, with fun options like Neapolitan ice cream-style coloring, reflectors, and strap add-ons like a cell-phone holster and accessory case ($80 for medium-sized bag; $10-$20 for upgrades and accessories). This should give you everything you rememberand morefrom that long-ago ad in Outside.
For a dizzying array of the best packs and luggage, check out Outside Online's 2005 Buyer's Guide.