Hi - one of the apps, and the one you may be most interested in, is San's POV Changer
http://il2fovchanger.byethost7.com/ - look at the screenshots, it's supposed to let you run multiple monitors & more... I think it's still in Beta, i've tried it, and it basically "fisheyes" the image. It's nest feature is that it allows you to use any (within reason) aspect ratio, without vertical cutoff (as in wide-screens - see his screenshots), or the weirdness on the sides (as i remember,
http://mission4today.com/index.php?name=...ls&id=2169 allows you to set up widescreens, but when you fly with no cockpit, you see weirdness...).
UDP Speed is something I haven't tried yet (i'm not at home right now - sick at my parent's house, so... no racks of 'puter boxen & trash-find monitors), but here's a link:
http://mission4today.com/index.php?name=...377&page=1. Devicelink is something I'm going to figure out, while I have all this free time. Again, the app is designed for linking with a second box, but you can point it right back to localhost (127.0.0.1).
As far as aspect ratio goes, a stacked pair of widescreens gives you basically a 1:1 square (16:18, but who's counting), as apposed to 4:3 which IL was designed for. Really wasn't a problem for me, didn't mind the cut sides. Anyhow, the first app will help that. You can, of course, do a bit better by putting the widescreens on their sides, and rotating the screens in the graphic card's control appy, but then the annoying line would be *vertical*, just where you don't want it to be.
Finally, the only really *usable* multi-monitor setup for a sim is a triple head, so you got your basic cockpit (or a quad-head, with the top screen, so you can look up!). Since I couldn't afford to go triple or quad, and the curiosity value of dual screens wore thin pretty quick, i stick to a single monitor, and try to be good by flying with the cockpit on. The fact that some gauges get clipped with a wide-screen setup never bothered me. Good luck and have fun,
-d.