Question: Is there any way to coax Gmail into pushing new-mail notifications into my Linux machine, without using a full-on graphical mail client like Thunderbird?

**edit**: Thanks for all the responses, but (unless I'm mistaken) these applications all *poll*, none of them receive notifications *pushed* from GMail.

Also, I'd prefer a console-based program, as this will be running on a headless server.

Answer: 
I know this question is quite old but it came up in my search and I thought I'd update. Evolution now supports IMAP+ or IMAPx which enables IMAP IDLE, and so gmail can push mail to it.

<http://chenthill.wordpress.com/2010/01/11/evolution-with-improved-imap-support-imapx/>
If you are on Ubuntu, try GmailWatcher;

ppa:loneowais/ppa