The Ntop guys have written a pretty cool vpn app that can get you access in a pinch.
Think p2p applied to vpns!
The ntop web page with excellent write-up
The Wikipedia page on n2n for the impatient
Trouble starting supernode in rc.local?, try this:
nohup /usr/bin/supernode -l 5000 & >> /var/log/supernode.log 2>&1