My kids are sci-fi geeks, which I think proves that I'm doing something right as a mother.
I'd say that a majority of our creative play here at our house revolves around one of their two favorite things - Star Wars and Doctor Who. They're hooked on both, and love to have lightsaber battles, freeze each other in carbonite, travel in the TARDIS, and battle the weeping angels. They keep me constantly entertained.
It was the combined love of Star Wars and Doctor Who that led to my kids' first mashup. It cracked me up, and made me so proud.
They were playing in the bathtub one night, when (for some reason) they decided to be Daleks. It made me think of this cartoon that I had seen floating around online.
So I told them about it (and explained what exfoliate means) and of course they thought it was hilarious. They both grabbed their sponges and started reaching for each other, shouting "ex-fol-i-ate!"
They did this for a little while, and then I heard my son say, in the Dalek voice:
"Ex-fol-i-ate! ... Ex-fol-i-ate! ... Ex ... Ex ...
X ... X-Wing Fight-er! ... X-Wing Fight-er!"
Then they went on to play Jedi vs. Dalek for the rest of bath time. It was epic.