Laptop Back Packs?

Cownonymous Award asks: "The company I work for recently gave me a laptop. Nothing wrong with that, of course. But: with it came a huge (and I really mean _huge_) laptop case, big enough to carry an RS/6000. Anyway, I look like a complete idiot when I take this humonguous "I'm a laptop, please steal me"-case with me. So I'm looking for an alternative, preferably a back pack. My question is: Has anyone had any (good) experiences with laptop back packs, especially ones like Eastpak's PC Pak'R or Timberland's HAKK?"