Shayne Terry - "Strong" , and Marcus Rowland's "California Cousin" are "Buffy the Vampire Slayer" crossovers.

Becky Bain - "Timeless" is a "Beauty and The Beast" crossover.

I wrote "Pie Isn\'t All That Easy" which is a "Pushing Daisies" crossover.

Wendy Richards' "At Wit\'s End In The East End" is a "Doctor Who" crossover.

I know there are many more; these are just a few that popped into my head right now.

As Lynn said, Marcus has a *lot* of crossovers (and they're all fun to read!)