I've been waiting a very long time for this! There is a long history behind the development and issues the developer Slitherine had with getting this game out. At one point it was about to be released by Eidos (who canned it as they felt GBA was the way to go) and even Take Two were going to release it...they wanted it to be a Duke Nukem game but the devs couldn't change things in time. Then it was canned, and the developer just went to making "meh" strategy titles (and really bad ones for the DS) instead.
Now however after 13 years a prototype has been released!
I'm not going to directly link to the site though as I am unsure of the legality of the ROM but GoNintendo has linked it and if you follow their link and go to the very bottom of the site there is a download:
That site also mentions a very nooby "Save T-Tex" Yahoo Group that I did myself with an ex of mine way back! God I was so young and naive back then!
NOTE: Only works with the emulator KiGB and Bung flash cards. I myself can't quite get it to go past the menu screen on KiGB but it works on my Bung card, runs OK but it is clearly not finished, it's quite buggy. This seems to be a very early version as I've seen video footage on IGN that looked smoother and showed the blasty bits on the guns. Maybe one day we'll see the full one appear.