Today, notifications from Facebook, Twitter and Groupon are received in email messages, but each website must be launched separately in order to use them. PowerInbox wants to change that.

PowerInbox is a tool that makes your emails more useful. Comment on a Facebook photo from your inbox, tweet and follow back via email and edit any message after you have already sent it. With PowerInbox, the apps for these services runs right inside the email messages themselves. Users can access their walls, reply to posts, view photos/videos and more on Facebook; follow, read and post Tweets; and check expiry and review stats for Groupons — all without leaving their inboxes.

“This is just the beginning,” explains PowerInbox Founder and CEO Matt Thazhmon. “We have built a unified open platform on which any developer can write their email app. Our vision is to empower users to play games, book travel, complete financial transactions and more, all from their email program.”

PowerInbox works on Gmail, Hotmail, and Yahoo Mail with Outlook coming soon.