We had one at the weekend, had a team of 5 doing CE Normal, made it all the way through to the last stage and one of our teams "friends" randomly joined us (yeah I know, we should have made it private only!) Anyway, he turns up and starts goign on and on about "whos got a Gjallarhorn" and all sorts of guff nonsense, basically slagging people off for not being lvl 32 yet and not having Gjallarhorns. Anyway, after about 5 mins of this we booted him and decided to make sure our group is private from now on. Guy was a total knob, first time I've ever had to boot anyone from the team.