I have a standard laptop bag from "Incase" that was made for an iBook that works well enough at the moment.
My problem is that I have too many gadgets with too many chargers. When I go out of town for a few days, I have to gauge the battery life and estimated usage on all my gadgets and decide what to bring, and what needs a charger.
Granted, I don't *have* to bring my PSP and Nokia 770 with me all the time, but it's sure nice to have.