Pretty much any Rodney Dangerfield joke works with Quark:

• I was so ugly my Moogie used to feed me with a slingshot.
• I was ugly, very ugly. When I was born, the doctor smacked my Moogie.
• My wife, Grilka, and I were happy for twenty years. Then we met!
• I told Dr Bashir that everyone hates me. He said I was being ridiculous: everyone hasn’t met me yet.
• I stuck my head out the hatch and got arrested by Odo for mooning.