At any given moment, I've got about a dozen windows open -- Outlook, a few browser windows, Word, Excel, OneNote, and some folders. Windows 7 promises to make finding an open window less aggravating, but until then, you can use Switcher, a utility that replicates the Mac's Expose in Windows.
Switcher not only duplicates the Expose experience almost perfectly, but it's a tiny download -- and it's free. When you invoke it, it splatters large previews of all your windows across the display, which you can switch to by clicking or pressing the matching number on your keyboard. The program is extremely configurable, with several display options, user-adjustable hotkeys, and an almost infinite amount of OCD-caliber customization, such as window opacity and animation duration.
As someone who uses the Windows 7 beta daily, I've fallen in love with the desktop improvements in the new OS -- but Switcher is so smartly done that it even beats the new "Aero Peek" taskbar previews.
Switcher requires Aero, so you'll need Vista or the Windows 7 beta to try it out. And try it out you should; it's guaranteed to make you more productive. [via AppScout]