Widgia

Boomerang for Gmail is a Firefox /Google Chrome plugin that lets you take control of when you send and receive email messages. It works for Gmail accounts and Google Apps.
Whether for personal use or business, Boomerang will work for you. Here are some cases where Boomerang might be useful:

- Paying bills on time
- Scheduled email in other time zones
- Send a birthday message while it’s on your mind
- Reminding yourself to follow-up with a client

Go to boomerang for Gmail for more info and the plugin downloads.