Initially, I've always thought dharma practitioners are really serious lot, like we don't laugh aloud or even joke. However, after being under a lama or guru, I discovered monks and nuns do have a good laugh now and then and jokes and made fun of each other alot. Now, that's an interesting find.
Dharma practitioners are just "human" after all, and we have humour too, LOL!
We do laugh alot about ourselves at that. Like many dharma teachers, Lama Yeshe, HH the Dalai Lama, etc. do laugh alot on even on their own jokes.
They know how to look at themselves in "funny" perspectives. That is the JOY we can experience in dharma.