You run on a public IP or over NAT? If NAT works, I could stick a little always-on Acer netbook in a closet to participate on the network over my 15Mb cable service. Would save a fair bit of money over dedicated server/VPS.
I've done it both ways. Either way, it's best practice to open a few recommended ports, so overall I don't see a ton of difference. NAT seemes to work just fine, so long as tor can establish a few outside connections. (A box sitting behind a NAT router has relayed about 10 GB of data since I reset it a few days ago, so obviously something is working).
Thanks for sharing.