Gmail now has functionality to import old email from another program into an existing Gmail account.
From Mashable.com here are 5 Ways to Spice up your Gmail signature.
Here's a tip for never again forgetting the attachment you meant to send. From the gmail tips page:
Turn on the Forgotten Attachment Detector in Labs, and you'll get an alert if you mentioned attaching a file but forgot to do so.
And did you know you can send an SMS right from gmail?
- Send SMS text messages right from Gmail.
How often do you try to chat with somebody and they don't respond because they just walked away from their computer? You can keep the conversations going with a Labs feature that lets you send SMS text messages right from Gmail. Enable it in Labs under Settings, and then typing a phone number in the chat box search window. We'll even save your friends' numbers in your Contacts, so you can just type names into the chat box and select Send SMS.