Best "featuring" performance

[Idiotastic]

So,what's the best performance you've seen featuring 2 or more artists who don't usually work together?

Got the idea for this after watching this video:


For me,this one.
Well,the first "band featuring artist",that is.

They're all rather unknown Belgian artists,so it wouldn't surprise if you nobody knows them.
And that's a shame.

search bar approved.

 

[xDHxD148L0]

I don't remember her name but there was a chick who came into the Dark Tranquillity "Where Death Is Most Alive" concert to do some vocals.