I'm not sure what you want to do. If you want to be able to connect to your PC's shares from anywhere, I can't help you (and I'll note that MOST users, though perhaps not you, have very limited upload bandwidth even on DSL/cable).
This is exactly what I want to do. I'm already able to mount my PCs shares from the Z and ssh into my Linux box from anywhere. I'm able to get about 45K/s upload on my connection, plenty for fairly small file transfers and streaming MP3s.
Does anybody know if using NFS instead of Samba would make any difference?