Hamachi... this looks interesting!
 

I need to check out their forums. What do you think?

http://www.hamachi.cc/

I heard all about this on a security podcast. Looks really really cool.

I just need to get this set up and going, to see how well it really works over internet connections (hotel to ADSL at home, for example).

Seems pretty interesting. Would be great to transfer stuff to another computer in a distant location for offsite storage or just transfering research/work from a work PC to a home system. But the P2P is what seems really interesting... Should be interesting to see how this and the Firefox P2P extension work and whether either become popular.