Does anybody know, and I’ve just started searching - but thought someone might have an answer, if there are any alternate programs I could use to texture a model I made for a game? Thanks!
Alternative to what exactly?? 
I do nearly all of my texturing with Gimp, though there are times when Zbrush is about a 1,000,000 times quicker.
So, for flat painting onto texture-maps I use Gimp or Photoshop (depends on my mood really :p)
For 3d painting straight onto the model, I use Zbrush. There’s bound to be free programs that let you paint straight onto it, but with 500 bucks laid down on Z, I don’t quite feel the need to keep lookin’…
I guess something that’s a possibility is downloading the trial version of Zbrush (only works for 30 days) or getting the trial version of 3dBrush (lasts forever). The only thing is, that you can’t export from either of them as far as I’m aware. HOWEVER, you can still work with them and get your model out…
How? you ask. Well, you can download a program called 3DRipperDX. It’s free and is a breeze to use. What it does, is run your program for you. It provides directX services to your program, which it then passes onto Microsoft’s standard directX libraries.
Now, this is where it gets tricky - not only does it pass the info on, but it also keeps a copy of it, building what is essentially a 3d print-screen of any models in the memory of your video card at the time.
When used with 3dbrush, you get a model that seems to be distorted - i.e you get the model after the viewing transformation has already taken place. I never tried, though I’ve got a sneaking suspicion that you could still use the program to create a texture map.
Probably a better option for the curious and/or technically inclined than someone that just wants to pump out a texture. Anyway, I had fun playing with it, perhaps you will too.
Simo,