I already sort of ran it past Aklyon and he was like "But I don't wanna do Minecraft!" XP
Anyways,
this is the mod I spoke of, Dawn of the Modern World. It has Rways (runways or roadways), Halogen Lights, and big garage doors. The latter are the main reason I want it. So we can have hanger doors without burying the map in redstone. And it does appear to have SMP support.
For extra futuristic touches, we could try
the Laser Mod and/or
PlasmaCraft. They're optional, though. One has to balance cool stuff and accessibility/workability
If you had to pick one, I'd pick the latter, since it clearly has more stuff.
The MOST important ones are...well,THE most important is technic pack (Which I am having trouble finding the topic for... D:), for that nuclear reactor goodness. (As it turns out, said nuclear reactors are in IndustrialCraft. I saw a
IC/Buildcraft mod while I was browsing,so we could just use that. Among other things, you can make oil from UU-matter with it. HUZZAH!. On a related note,
Equivalent Exchange apparently works in SMP now, HUZZAH! Albeit with... issues.) After that, I'd say
Planes. I'm pretty sure they both work in MP, though Technic Pack may require the loss of a few things, as we discovered when Aklyon tried to get a Technic server up.
EDIT: Here, have a list in descending order of importance. Yeah, I know, it's not what I said up there. I didn't realize just how much stuff PlasmaCraft has. XD
IC/Buildcraft mod -->
PlasmaCraft --->
Planes ->
Dawn of the Modern World ---->
Equivalent Exchange ------>
Laser ModEDIT EDIT: Yet more mods.
Smart moving, for vents and climbing and etc. Pretty cool and allows for some nice stuff, but isn't THAT vital, or shouldn't be.
Insert mod for SPACE! when I find one here.