Runescape used to be exciting and an andrenaline rush, but not so much anymore,
Recently I've been server hopping and a good majority that I've played have been well populated, for the last month or so I've been playing a pretty fun old school server called, CreativeScape -
http://sythe.org/showthread.php?t=1174173 If you liked old school PKing, you should give this a shot.