The one my mother thinks is hilarious is the time I dreamed I was pregnant, in the hospital, and delivered a litter of kittens. When she was pregnant with me, she also had the same dream. Apparently it's genetic.
DH's favorite is the dream where I "wake up" and I'm in bed with ex-BF, only in my dream I'm married to him and living in this run-down crummy apartment, and I start crying in my dream and complaining how I had this lovely dream that I was married to (real DH) and he was so nice and we had this big house. Ex-BF gets mad and starts yelling that I must be cheating on him with (real DH) and so on, until I wake up.
I rather like the ones where I meet dead relatives. There was one especially sweet one where I go on a business trip somewhere and run into a wise old lady who introduces me to a young boy (about 9-10 years old) and tells me that he is my dad, reincarnated. I give the kid a hug and tell him to study math and science very hard, because he'll find a natural gift for it, the boy's parents make me a cup of tea, and then the old lady tells me I have to get back to work.