How do crabs get around on land? 

They use the sidewalk.

What did the lazy anesthesiologist say before surgery? 

Knock yourself out.

A factory worker got his arm caught in some machinery, severing it just below the wrist. Unable to work, and with no income, he knew he had to see a prosthetic specialist as soon as possible. 

Sitting in front of the doctor, he explained that no one was willing to hire him unless he had use of both arms. 

The problem was that, until he could get a job, he wouldn't be able to pay for a prosthetic. 

"I'm desperate, Doc. Could you lend me a hand?"