This little app is a must for Windows users that have multiple tabs open on their desktop. It is pretty much the same thing you get with Compiz on Linux and Expose on Mac. There are a bunch of settings but I didn't even bother. I got what I need from it. Highly recommend. Get it here.
UPDATE: I have a mainframe console running on my machine at work that's called TSO (Time-Share Option), so the keys to navigate are F10 and F11 for left and right. This brings me to an interesting point, you may have to reassign keys for DExpose2 to use other shortcuts. Btw, in default DExpose2 install: F10 initiates Expose, F9 brings you back to the way the window was before and F11 shows desktop.