Yo mama's so stupid she got locked in a supermarket and starved to death.
(yo mama's so poor that) The other day i saw yo mama walking down the street, kicking a can.
I yelled out: "Hey {insert name hers}'s Mama! What are you doin!"
And she yelled back: "I'm movin house!"
These kind of Mama jokes are stupid and funny at the right occasions.
Generally if we really want to abuse someone using his/her mother (usually his) we accuse her of being a prostitute or talk about us fucking her. ("What are you doing?""Your mum" for example. Usually funnier or wittier though) I only know a few people we'd sink that low to abuse like this though, and they deserve it.