Using rsync and which directories should I place in my exclude file when using rsync?
I don't think this is the complete answer, but some are:
/sys
/proc
/tmp
/var/run
/var/lock
/dev
/mnt
# The following are stolen from Womble:
/var/cache
/var/tmp
/var/spool
Add /var/cache, /var/tmp, and /var/spool to Kyle's list.