For those of us running a multi-monitor setup, I've found a bit of software called SoftTH, which I believe enables DirectX on up to 3 screens, so you can go full screen across the board
It does take a bit of configuring, and so far I'm banging my head against a wall to get it to work on Fallout 3, but I've got it working on Live for Speed (The trial version), and Oblivion...
And the results are great - Even if my driving on LFS isn't
Anyhow, take a peek here : http://www.kegetys.net/SoftTH/ (Note, at the moment it's only for Dx8 and 9 games
And a couple of example videos here :
http://www.youtube.com/watch?v=PHJH8wHw_eY - Oblivion
- Live for Speed
And the setup :
http://www.mr-pot.co.uk/images/screens.jpg
Running 3 x 24" Samsung monitors at 5760x1200px on 2 nVidia GTX 260's, although for SoftTH you only need one decent card, and a token 2nd card to fire up the 3rd screen - Haven't measured frame rates or so on yet, but it's totally playable