Mr. Hartmetz on his Longranger, we jokingly call him 'The Voice of God'.
Other nicknames are (but not limited to) H, Hartmetz, 'H' ('Ah-ch-ay, Spanish pronounciation lol), Sr. 'H', Banana Man [although he hasn't worn the raincoat in ages...], BFG (Big Fricking Giant), The Big Penguin, etc.
Gotta admit, band will never be the same without the insane genius behind it...or is it in front since he's the conductor? XD
EDIT: Oh...a picture? Right. Lemme dig up the one from Charlottesville...
...which is no longer existant, of course. So here's a less lulzy one.
Picture since I do not wanna pagestrechLOL I didn't realize he looked so much weirder than usual in this picture :< The other one was funnier but...I deleted it a while ago, I think.