One as jungle Volibear. It was kinda handed to me tho, the support probably could have escaped but i got my flip off and he didn't put up any resistance. That chain lightning OP!

I was just in a game with some friends and my brother got one as Lee Sin, it was fun to be apart of anyway. :p
I've only acquired a penta in an ARAM.

The closest I came to a penta in a ranked game, I had it stolen. I was playing Graves and got a quadra and the enemy Annie picked up a quadra as well. It was a 1v1...

And she killed me for the penta. There was a lot of screaming at my computer.
One as Support Katarina
Another as Sivir
and one as Pantheon during custom game ARAM, before the lissandra update, ult for a quad and have shen taunt last person so I can get the Penta.