OK, let's break it down. I'll comment on the ones I know.

diablo 2 - not sure if it allows multiplayer without the CD in place... maybe.

mythos - Mythos might be dead, with Flagship going down.

neverwinter nights 1 and 2 - though they allow LAN multiplay, I'm not sure about the CD requirements. It seems to me that the latest NWN 1 patches disabled the CD check, so it might be possible, but I'm not sure.

Freelancer - nope, you need two CDs. Not sure about LAN play either...

Europa Universalis 3 - if you buy the download version from Gamer's Gate, you can install in two computers without the need for CDs. It can make for a long/difficult play, though, unless you agree on speed settings and such. But it's a pretty good game.

Mount and Blade - No multiplayer. Fantastic game, anyway, so it's highly recommended nevertheless.

Sins of a Solar Empire - I think you can install in two different computers... just not sure about simultaneous LAN play.

The Witcher - no multiplayer either, but it's a fantastic RPG, one of the best I've played.

grim fandango - No multiplayer, since it's an adventure game from Lucasarts (and a pretty good one, too).

Dark Reign - wow, this is an old, old RTS (before Starcraft, even... I think it was released in 95 or something). I can't remember if it has LAN play, but I think it required the CD in place to be played... not sure, though.

Hey, can anyone tell me a good website for looking up games?

actually all games ive come across  

If your talking about older games, then this is correct! However, greed and stupidity drive game developers in the direction of not allowing this with allot of newer games.

Having said that, i am not exactly sure how many games are like that, all i realy know is that Command and Conquor will not allow multiplayer LAN game from 1 disk. The bottom line is that this is a very difficult peice of information to learn about a game before buying it and that is the whole point of this thread!

I want to know what games do and do not allow LAN multiplay from 1 game disk? or a good website that has that kind of detail about games that i can look up myself?

Supreme commander does alow you to play with out disk but you have to download the patches for it. Also its multiplayer sux, cus the other plaers game play realis on thother peoples cpus so it will be slow. my old computer about blew up from playing that game on high.

Published by Stardock, yep. It also has no shareholders, since it's a privately held company, which means it's only influenced by what Frogboy wants to do pretty much. In this case, he likes the copy-protection free way of doing things

Yea, i am familiar with Stardock because of Galactic civilisations. Although Galviv1 and Galciv DL are not multiplayer games so the question of LAN play simply isn't there.

But it is not all good at Stardock, one thing that happened after i got Galciv DL was 'Stardock Central'. I bought the expansion from DL, i forget what it is called now (DA, dark avatar?), but they stopped the stand alone downloads and you can only download through Stardock Central. This is a slight problem when Stardock Central thinks all your codes are invalid and all the codes Stardock support sends you are all invalid as well, hec even the codes for my original Galactic Civilisations installed from the disk i bought in the shop was invalid as well! go figure!!

I never had time back then to persist in trying to solve that problem and now i have moved on to being interested in multiplayer games. Perhaps i might check back one of these days and see if they have it in a stand alone download yet? So i can install it without having Stardock Central telling me the codes are invalid!