Testing of Microsoft's Office 2010 suite wasn't supposed to start until July and on an invite-only basis, but in what's become a pretty common pattern, leaked copies of the still unfinished software have already trickled onto a number of torrent sites. Both the 32- and 64-bit editions of the application suite were available for download earlier than planned, mirroring Windows 7, which has had all major development milestones as well as numerous interim builds leaked ahead of the official releases.
It's not known if the leaked version, build 14.0.4006.1010, is the same that Microsoft will begin delivering to select testers at the start of July. Among the notable changes in Office 2010 are a revamped Outlook e-mail client that will feature the "ribbon" interface, and the simultaneous availability of new, browser-based versions of Word, Excel, PowerPoint and OneNote.
If you are interested in trying the leaked version, a quick look at your favorite torrent site should yield some results - know that this is not exactly considered legal, though, and be sure to double check your source to avoid any potential Trojan infections.