The new fonts included with Windows Vista are called Calibri, Cambria, Candara, Consolas, Constantia, and Corbel, and even though you don’t have Vista you know you want them.
These are the new and improved fully finished versions. Update (March 31, 2008) If you want an official source for the fonts install PowerPoint Viewer 2007. The fonts will be automatically added to your Windows system. (Disclaimer: Read the legal fine print on Microsoft’s site for usage rights.)
Wikipedia entry on Calibri.
Wikipedia entry on Cambria.
Wikipedia entry on Candara.
Wikipedia entry on Consolas.
Wikipedia entry on Constantia.
Wikipedia entry on Corbel.
Previously: Windows Vista Fonts Now Available and Microsoft Office Compatibility Pack.