Amy Winehouse is one classy lady. As The Sun reports:

The junkie singer, 24, is to be quizzed by police after claims she HEADBUTTED a Good Samaritan who hailed her a cab outside a bar.

Rehab star Amy, said to have PUNCHED a second victim in the face, sank to a horrific new low while high on Class A drugs.

How great is that? Some sorry dude hails her a cab and she turns around and headbutts the fool.