Jokes that Seemed Funny at the Time

Have you ever come up with an obscure joke, just off the top of your head, but you can't think of any way to fit it into conversation? I must have a million of them:

Q: What do you call a singing salt water solution?
A: Saline Dion.

"I wanted to be an object-oriented programmer, but I just didn't have the class."

Q: What do you call a really short linguist?
A: Gnome Chomsky.
Q: What do you call the DNA code that made him that way?
A: Genome Chomsky.

...Okay, so I only have three. Any suggestions?