Parsley

Opening your inbox is distracting and takes time away from the more important tasks you have to do. With Parsley, you can go almost the entire day without ever opening your inbox. Parsley gives you the ability to act quickly on incoming messages that need it, while saving those that need more time and attention for later.

Parsley integrates with your existing mail client to provide a better email experience. If you're using Gmail, then you already have access to the world's best email client. That's why Parsley works seamlessly with the Gmail Web app providing instant notifications of incoming email and allowing you to quickly preview and respond to each message, all without ever having to open your inbox. Parsley also works with most traditional desktop mail clients.

Features:

• True push. Unlike most notifiers we use IMAP IDLE. This means you get your email faster and use less resources on your computer. Most notifiers run in loops repeatedly asking the server if any new mail has arrived. This is inefficient. By using push, all the work is done by the server and your computer just sits back and waits for the notifications.
• Fast and lightweight. Because Parsley uses push notifications, it reserves your processor power and memory for all the other important tasks you're doing. And when you're ready to use Parsley, you'll find it very quick and responsive.
• Growl. Beautiful notifications (and sound), summarizing the incoming email.
• Full message preview. If you want to see more, just click on the notification (or assign a keyboard shortcut) to see the full HTML message in a popup.
• Unread count. Missed clicking on the notification? No problem. Unread count in the menu bar lets you know when you miss something. Previews can be brought back up with a keyboard shortcut, or notifications can be redisplayed using the menu bar.
• Actions. In the preview you can archive, delete, mark as unread, star, reply, or forward - all without opening your inbox.
• Go to inbox. Sometimes you need to do more. A handy keyboard shortcut, or click in the menu bar option will take you to your inbox.
• Keyboard Shortcuts. For those who prefer the keyboard, Parsley uses the same shortcuts as Gmail in the browser. Parsley also adds handy global shortcuts for bringing up and dismissing popup windows, opening your inbox, and composing messages.
• Mailto: links. For those of you who prefer Gmail in the browser, now you can make it your default mail client. Click on any mailto link you come across and have it open in Gmail automatically.
• Runs in the menu bar. Optionally it can run as a System Preference Pane and be completely hidden.
• Priority Inbox support
• Works with Google Apps accounts