Mac OS X only: As the name suggests, free plug-in iPhoto2Gmail adds Gmail integration to OS X’s default photo management software, iPhoto. Windows users enjoy no-nonsense integration with Gmail via Picasa, but since Google hasn’t made the OS X jump with Picasa, iPhoto2Gmail makes adds the functionality for you. The plug-in supports your actual Gmail contacts and optionally resizes the photo before you email it. If you’re a Gmail lover who hasn’t set up Mail to send email, this plug-in is just the ticket. iPhoto2Gmail is a free download, Mac OS X only.