The problem with playing 13-year old game is that like many teens, they're anal retentive when it comes to doing things. So imagine my annoyance when I was told to enter the IP address manually to play a multiplayer game. So let's set a time and date when we can have a game together. Somebody create a server please, my firewall hates me.
Online play questions can be addressed here.

On the sidenote, it'd be nice to have a service on the GOG downloader that works like Steam's friends list. I know there are alternatives, like using IRC to arrange games, but nothing's better than home cooked ham - and the same can be said for a GOG matchmaking service
I'll probably be getting DN3D on the next pay day, so I could play with you then. Does DN3D have co-op?

Yes, there is co-op in DN3D.

you know, you could just run the DN3D through steam..

I wasn't just referring to DN3D in particular. Besides, not every GOG user uses Steam

I think most GoG users who don't use Steam wouldn't be likely to install any other 3rd party distribution software...

Agreed.

Or a dedicated GOG multiplayer server with a static IP that games can connect to

Rightly so!
But then I'd rather play with people nearer to me, like you or michael, for smoother online play. An official GOG server would probably be in either Europe or NA

While that would be nice... They'd need to run a server for each and every GOG game that supports multiplayer. Not going to happen. Besides, not all games have dedicated servers. Duke3D doesn't, for instance.

Yeah having had another look at the catalogue, there's more games with MP than I thought.
Maybe a website app that lets you arrange games. Shouldn't be TOO hard to code, get the game, get the desired game type (where appropriate), get the local time you want to play & process it through a timezone converter so it spits out the viewers local time & spits out the IP address you need if you say you want to join.
Can't remember if timezone is part of the profile though, that'd have to be added to the profile if not, that or just added to the game arrange page but that'd be a bit clumsy