I keep one of the big 15X15 ziplock bags in my laptop bag,
incase it rains.

I use a couple of LockLock boxes for chargers and other
small stuff, and an otterbox 2000 for my PDA, and a
small witz case for ciggaretts and a lighter.

While I don't really think the ziplock is needed for
short trips in light rain, say, from the car to the office,
I keep it around since it weighs hardly a thing, and
if it's needed, it would be really bad if I didn't have it.

Mogg