Descent 2 for DOS, Windows, and Unix (Linux, Solaris, Mac OS X, etc).
d2x can also run on handhelds like the Pocket PC and the Nokia internet tablets.
This project does not often have up-to-date binaries available, I
always recommend compiling from SVN to get the latest features and
bug-fixes.
What we do have is available here.
svn co svn://svn.icculus.org/d2x/trunk d2x
You can browse the source code online, with ViewVC
If you are a past contributor to d1x or d2x, your old cvs login does not tranfer over. Send me an email and I can give you access to svn.
You can also browse the cvs history of d1x online, with cvs2html. It is generated once a month or so.
If you fix a bug or add a feature, send it in a patch! Either attach it to the relevant bugzilla bug, or send it to the mailing list.
Questions about d2x can be best answered on the descent-source mailing list. see the D1X Developer Resources page for the archives and subscription information. org.