I just started watching Warehouse 13 recently and had a thought that I'm sure many people have already had, that theoretically the warehouse at the end of Raiders of the Lost Ark could be Warehouse 13. There's probably a line at some point in the show that makes that impossible, but it did get me thinking about what sci-fi/fantasy franchises could co-exist.
For example, some months ago there was a thread in the Doctor Who board about shows you'd like to see DW cross-over with, and I mentioned Primeval. They're both British time-travel series, the same raptor model was used in both, the weapons used in Dinosaurs on a Spaceship were very similar to the ones from Primeval which were based on technology from the future, a device in Primeval used to exert limited control over the time anomalies was also seen as part of the 11th Doctor's TARDIS console, and the DW serial Invasion of the Dinosaurs had a very similar plot to Primeval with holes in time transporting prehistoric creatures into the present day. Obviously Primeval had no mention of alien invasions, but Doctor Who has shown parallel universes where not all events are the same, so theoretically the two could take place in the same continuity.
What other examples are out there?
For example, some months ago there was a thread in the Doctor Who board about shows you'd like to see DW cross-over with, and I mentioned Primeval. They're both British time-travel series, the same raptor model was used in both, the weapons used in Dinosaurs on a Spaceship were very similar to the ones from Primeval which were based on technology from the future, a device in Primeval used to exert limited control over the time anomalies was also seen as part of the 11th Doctor's TARDIS console, and the DW serial Invasion of the Dinosaurs had a very similar plot to Primeval with holes in time transporting prehistoric creatures into the present day. Obviously Primeval had no mention of alien invasions, but Doctor Who has shown parallel universes where not all events are the same, so theoretically the two could take place in the same continuity.
What other examples are out there?