Obligatory sexist brain joke
Bright astrophysicist is referred to brain surgeon. He gives her the bad news: she has early onset dementia. She is understandably upset, and the surgeon, who is a bit of a shady character, says "look, I shouldn't tell you this, but there is a highly active market in second hand brains. I've got a contact..."
In the second hand brain shop....
"Well, my dear, we have this one: 1.30kg, female brain, some kind of business genius --- $10,000"
"Have you got anything more science-based?" she asks.
"Well, if you don't mind spending a bit more, we have this one, 1.31kg, female mathematician, $20,000"
"Hmm, good" she muses. "What if money's no object?"
"Ah", says the brain salesman, eyes lighting up "Well, in that case ..." and he opens a safe. "This is the brain of a male nuclear physicist. It is $50,000 for 1.4kg of brainpower"
"Wow" says our heroine, "why is it so expensive --- is it the extra 100 grams?"
"No, bless you my dear" says the salesman "It's a MALE brain ... it's hardly been used!"