6. Torchwood Meets Community
Community: Yet another NBC comedy series, this one all about the exploits of a Spanish class study group. Originally a somewhat stereotypical sitcom, by the end of the first season it had expanded into a show capable of doing intelligent parodies of nearly anything. Old video games, Die Hard, Christmas movies, bottle episodes, zombie attacks, Ocean's Eleven, mafia movies, George Orwell's 1984... and many others.
Torchwood: A BBC series, spun off from Doctor Who. Torchwood aims for a more mature audience than Doctor Who, and has thus alienated a sizable portion of the former show's audience. Nonetheless, the plot of Torchwood essentially follows a group of agents investigating alien-related mysteries on Earth. Kind of a British, non-humorous Men In Black.
The Crossover: Wow, this one would be so easy. Have a group of aliens attack Greendale Community College and hold it hostage, with the Torchwood team trying to rescue everyone inside. It would be a unique attempt at humor for Torchwood, and if you think an alien hostage situation sounds too strange for Community, you clearly haven't watched Community.