An ounce of brains
A lawyer finds out he has an inoperable brain tumor.

It's so large, they have to do a brain transplant.

His doctor gives him a choice of available brains.

There's a jar of rocket scientist brains for $10 an ounce.

A jar of regular scientist brains for $15 an ounce.

And a jar of lawyer brains for the sum of $800 an ounce.

The outraged lawyer says, "This is a rip off! How come the lawyer brains are so damned expensive?"

The doctor replies, "Do you know how many lawyers it takes to get an ounce of brains?"

After many years of trying to find steady work...
After many years of trying to find steady work I finally got a job as a historian until I realized there was no future in it.