Gmail Users - How Often does Gmail collect my POP3 mail ? Çap et

Gmail has an algorithm for figuring out how often it should check your email from the server. You can read about it here: 

http://lifehacker.com/5346103/make-gmail-check-your-pop-accounts-more-frequently

Here's a browser specific plugin that will force it to check more often: 

http://www.danielslaughter.com/projects/gmail-pop3-checker-for-greasemonkey/