I know there's no native widescreen resolution, so is there a way to run Fallout in a windowed mode? I've tried using D3DWindower, but it either runs the game fullscreen or gives me an error message when I try.
Anyone know how to get Fallout looking nice on a widescreen monitor?

Try this: http://www.nma-fallout.com/forum/viewtopic.php?t=42386
You can play fallout in almost any resolution you want.

Thanks... now if only I can get windowed working...

Try right-clicking the executable, go in to properties. There should be an option to run it in a window.

So, no one knows of a widescreen mod to use?

"Crow" gave you a link to what you need.

The patch works well, thanks!

The patch will allow me to run at my desktop resolution (1440x900), but I wasn't able to get any lower resolutions working. Has anyone?

This is kind of a stupid question, but did you try editing the fallout_res.ini?

I haven't tried it as windowed but it claims to be able to make it work, check out this:
http://timeslip.chorrol.com/sfall.html
I used it to manage to get rid of the screen going black by changing the ddraw.ini that comes with it and using its ddraw.dll. (sure the movies get pixelized, but I can live with that)

Yes sir. I should say I was able to get 1024x768 to work, but I wasn't able to get any widescreen resolutions working below my desktop resolution.

Delete or rename ddraw.dll from your Fallout folder. Look in this topic for more details.

i tried -- nothing lower than that resolution would work. the best option if you don't like everything on screen to be really small (like me) is to run the game at 800x600. the top and bottom of the screen will still be cut off a bit, but it won't affect gameplay like playing at 640x480 would (when running 640x480 using a widescreen monitor, there are several maps where you can't reach the bottom of the screen to advance to the next area because running in a 4:3 ratio seems to cut off the top and bottom).