I'm using Plucker to have some docs when visiting customers and/or reading at spare time.
It's a very intersting thing, sinc it can convert any HTML (even with graphics) to a document in your Palm compatible handheld.
Since I have 16 MiB of storage space (8 MiB of RAM + 8 MiB of memory stick), there are lots of things that I can have there. I've gotten near 4 MiBs of documents from TLDP and I'll be converting FreeBSD's handbook too. ;-)
VERY nice reference docs in the palm of your hand. ;-)
UPDATE: It's already done. You can get the .pdb file here.