I have a VM running my webserver, mumble VOIP, IRC server (inspircd), two IRC bouncers, OpenVPN, Xymon monitoring, bitlbee, and a few other things and it only has 768MB RAM.

last pid: 91361; load averages: 0.28, 0.28, 0.25 up 9+19:03:28 14:37:36 74 processes: 1 running, 73 sleeping CPU: 0.0% user, 0.0% nice, 0.0% system, 1.2% interrupt, 98.8% idle Mem: 38M Active, 512M Inact, 133M Wired, 8404K Cache, 87M Buf, 32M Free Swap: 2000M Total, 71M Used, 1929M Free, 3% Inuse

2GB is enough to run a LOT of things.