You know he was in town for a screening of his upcoming used car salesman movie, The Goods: Live Hard. Sell Hard.

And while he was here, Jeremy Piven — a.k.a. Ari on HBO’s Entourage – ended up on stage at Tootsies Orchid Lounge on Lower Broadway.

Jeremy went there with actor Ed Helms, or Andy from NBC’s The Office.

Jeremy ended up on stage, playing with two different bands. Among Jeremy’s selections: Stevie Wonder’s Superstition and that ZZ Top “I ain’t askin’ for much” song.

The super-packed crowd went nuts.

And Jeremy loved it, too, telling the crowd, (in a loose translation):

“Thank you so much. for me, this is Make-A-Wish… To be able to play my heart out on this stage is awesome.”

Then, there was an Entourage-like black convertible parked outside, and the Piv hopped in for some pics. No dramatic drive-off: The car battery was dead.