i use the fisher pens for most of my writing.

Stowaway (basically a refill with a plastic coating) in my daypack

military style retractable for work, every day use, etc

bullet pen when i need to just throw a pen in my pocket and go. since its smooth it doesn't poke holes or get caught up in my pocket.

oh, and the rei (rite n the rain) pads for backpacking

and, of course, always have a pencil as a backup <img src="/images/graemlins/wink.gif" alt="" />