Hacker News Reader

http://mcserverlist.net is the most popular site for listing

There are also several sections of the official Minecraft forums dedicated to finding or hosting servers.

http://www.minecraftforum.net/forum/49-starting-up-looking-f...

In case anybody feels like getting together with for a HN minecraft session, I'm hosting a server here: 78.46.43.181

Currently its just me and my friends (when I persuade them to throw away their time and get Minecraft). I will leave it running anyway in case somebody feels like joining. The machine I'm running this on is fairly high spec and is otherwise idle (only hosting one very very low traffic website on it), so it "shouldn't" lag, st least, not from lack of resources. Hosted in Europe, so ping may be a bit high from the US.

Google.

http://lmgtfy.com/?q=minecraft+servers