Multiplayer Angband could kick ass, although the planning could be an issue.
Like, say,
Mangband? Never played it, but it's there. There's a few more multiplayer roguelikes meandering around, but I can't remember any at the moment. There were also a couple of MUDs that was basically roguelikes, Pits of Angband or something? Angband map/item generation with standard hack'n'slash MUD combat. The one I managed to play any was pretty impressive, but they all seem to be defunct these days. Was a bit of a downer when I got around to checkin' on 'em and they had all went up in smoke.
I've spent far too much time on angband variants, though. I started roguelikes on one of the very early versions of zangband, iirc, and I've at least died a few times on
most of them, which is actually vaguely ridiculous. There's a junkload of *band varients.
Steamband, cthband, Portralis (Actually a PernAngband -- ToME, these days -- fork, and
radically different from Angband's playstyle, but still...), and Furyband are more-or-less my favorites among the ones I've played. Furyband and an older version of Steamband (When water naturalist regen was flipping insane) are the only ones I ever won with... and even then, only once a piece, both ridiculously cheaply (Around the corner morgoth kill in the former, lightning-storm (iirc) artillery
from the other end of the map in the latter. Good stuff.). Hengband -- and whatever it is that it was based off of -- was also awesome. *bands need more stuff like Heng's classes. Ninjas were flipping awesome.
There was one that I keep forgetting the name of... ah! Kamband. That one was vaguely awesome, but absolutely ridiculously hard -- item damage is in by default, and the more damage you do, the worse the item comes out (Certain race/class combos, golem/werewolves ferex, could destroy their starting weapon in something like two hits). There's even an option to have artifacts operate under the same rules; imagine disintegrating Ringil or something on a cave lizard's skull and you get the general idea. Lots of other neat stuff; multiple town maps, randomly generated wilderness, multiple quest lines... it had a lot going on, with the caveat that it's even more brutally difficult than normal Angband.
As for base angband, the original? Meh. Kinda' boring
Awesome considering the time it came about, the same with rogue and moria and junk, but so much more has been done by now...