Like others, I'd recommend a 512mb Linode. It doesn't sound like a lot, but it's enough to run a well-architected app, and if you need more juice, you can alway

Like others, I'd recommend a 512mb Linode. It doesn't sound like a lot, but it's enough to run a well-architected app, and if you need more juice, you can always upgrade to a larger Linode. $20/month is dirt cheap for the quality of platform you get with them. You can throw a small Adsense ad on it, and if the page is getting any traffic, that'll help diffuse costs. I've got a hobby project that does about a half million pageviews/month (which isn't bad, since it's a single-page JS app) and it pays for itself about twice over with a single 300x250 in the bottom right-hand corner.