Yo Momma's so poor, when I rang the doorbell she leaned out the window and said "DING!DONG!"
Yo Momma's so poor, she's got more furniture on her porch than in her house.
Couple of old ones: Yo Momma's so ugly, they filmed "Gorillas in the Mist" in her shower. Yo Momma's so ugly, they push her face into dough to make gorilla cookies.
Yo Momma's so stupid she comes to you for financial advice.
Yo Momma's so stupid she plays chess on Gameknot.