Mailplane

If you're a Mac user and a Gmail fan, I would highly suggest you head over and check out Mailplane. This application adds all of the functionality to the Gmail user interface that I've ever thought was missing.

Basically, it's a separate app that presents you with a browser window that shows your Gmail account...all of the widgets of course now use proper Mac styles, and allows more advanced interaction through the use of buttons on the toolbar and drag'n'drop functionality.

For example, need to send a partial screen shot to someone? Start composing your message, click the screen shot button, and drag the area you want to send. Nice and simple.

Have multiple Gmail accounts? No problem, just double-click each account in the drawer to switch between them. (It also offers the possibility to add all passwords to the Mac keychain.)

Full Growl integration is also nice as I use it as my master notifier on my system.

Mainplane is in beta right now (invitation required, but it only took me 24 hours to get one sent to me), it will be shareware when it hits public release. I'll definitely be dropping the small cost on it...I'd argue that it has saved me or Canadian Tire that much money in the few days that I've been using it.