Get mail from other accounts
Now Gmail can check for the mail you receive at your other email accounts. You can retrieve your mail (new and old) from up to five other email accounts and have them all in Gmail. Then you can even create a customized ‘From:’ address, which lets you send messages from Gmail, but have them look like they were sent from another one of your email accounts. Please note that you can only retrieve mail from accounts that have POP3 access enabled.
A more detailed step by step instruction of doing this available in the Help Center.
Unfortunately, the fineprint.
This feature is currently only enabled for a limited number of users. We’re working on making it more available soon. Look for it in the ‘Accounts’ tab in Settings.
Anyway, I shall be waiting for this feature. It will help me check a few other POP accounts. I’m also hoping their antispam filters will help in this. Yahoo! Mail already offers POP3 checking. However, it’s spam filters aren’t automatically applied to incoming email.