I've been trying to get people to play some of the older games that I enjoyed and I hopefully think others will as well. Right now I'm trying to get people to play Duke 3D cooperative or deathmatch, I'm pretty open in that regard.
Anyway, here are the links you need to get going with duke right now:
duke3d hi res: http://goo.gl/jKqb
eduke32 mp exe http://goo.gl/JtB8I
atomic edition http://goo.gl/EsqZW
Now, Install the hi res version first and put it into a directory you'll remember (preferably not Program Files etc). This will install the game and the shareware version of the game. The atomic edition link I provided is most likely considered warez, although I think it really should be abandonware at this point. If you don't feel comfortable downloading that version, find yourself an atomic edition of duke3d (you're looking for the .grp file that is about 42-44MB.
After all of that (sigh) then you can download the version of eduke32 that I've linked in this post. It offers master/slave and p2p types of connections, but the master slave version works much better. If anyone is interested in some of this old school type of fun please let me know since you have to run these programs all in succession. Also, Doom/Doom2 I'm always open for as well. :D