Comment Try North Face (Score 1) 642
The north face recon bag is a bit more than you wanted to spend (approx $70-80), but comes with a lifetime warranty (i've taken advantage of it-they're pretty great about letting you take it back for whatever reason). It has a padded laptop part, is extremely well constructed, has nice pockets for all the associated gadgets (cell phone, pda, etc), and seems pretty water(proof|resistant).