The Shaun Jackson Design / Higher Ground Laptrap sleeve looks interesting—an entire mobile workspace folding out from a single backpack—but it also lacks an important feature in any bag of mine: the ability to cram lots of extra crap inside. So if you’re a meticulous sort, willing to wrap cords and exert some measure of pre-trip planning, it might be worth a look.
The bags start at $60 (plus an additional $15 for the backpack strap) and are listed in sizes for Powerbooks, but should fit any standard 15- and 17-inch PCs.
Product Review: Laptrap Laptop Sleeve [PowerbookCentral]