I recently purchased an all-black "Eminence Tote" from The North Face. As a college student, the $75 (including shipping) was a little steep for me, but it has definitely been worth it. As of today, I am comfortably carrying a 15" MacBook Pro, a travel umbrella, fleece jacket, 3" binder, assortment of lip balm/earbuds/mints/powerbars/other small goodies, bag-o'-writing utensils/post-its, and full-size laptop charger... And I have a bit of room to spare! The bag has a laptop compartment, several zippered pockets both inside and out, and a few other small good-to-have features.
The best part of this bag, in my opinion? 100% recycled fabric that's super sturdy and dirt-resistant.