http://prgmr.com/ doesn't have space available right now, but they have VPS plans starting at $5/month and I've heard good things about them from people on HN.
Seconded. I have a server on prgmr.com right now that's running node.js and I've been very pleased. Fast servers and and perfect uptime, so far. Sign up for the waiting list if you're interested. The only konck against them besides the waiting list is that it takes a day or so from when you purchase the VPS to when It's ready.
Prgmr is great if you need a small affordable instance and don't need to worry too much about performance (http://journal.uggedal.com/vps-performance-comparison). I use one 256MB instance ($8/month) as a development box.
They are great I have one that I use for fun stuff and netbsd is a pretty easy setup if you want it. Once they email you that they have new VPS's be sure to sign up pretty quickly though because they run out fast.
Yes I've been on the waiting list for one of those for a while, even with Heroku supporting Node.js I would get one. It is a very good price and it's always nice to have a small VPS for random stuff.
