I found this nifty trick for mounting OS X directories from Linux. This is handy when you're using Parallels on your machine and want to easily pass information back and forth. Parallels comes with a utility for doing this from Windows, but not Linux.
The idea is to use sshfs, the SSH filesystem. I installed it easily on Ubuntu using apt-get (on Fedora, you'd use Yum) and then mounting a disk on my OS X file system is as simple as
sshfs email@example.com:Documents "OSX Documents"
"OSX Documents" is an empty directory on the Linux machine that serves as the mount point. "pjw" is my user name on my Mac. You can do the usual SSH stuff to avoid typing your password all the time.
It works great. There's nothing specific to Parallels here, of course. This would work whether the Linux machine is virtualized or not. You could, of course, use "Personal File Sharing" on OS X and mount the OS X drive as using Samba, but I like the simplicity of SSH.
Now, if I could just get cutting and pasting to work...