Though there was never a comic book based on it (and only a single novelization), I would love a crossover between Star Trek and the 1980s War of the Worlds television series. To be frank, I wished at the time it was on the air that Paramount had done a crossover episode between TNG and WotW.
I'm just as glad they didn't. I kinda liked the first season at the time it aired, more for the cast than anything else, but when I revisited it a few years ago, I realized it was
awful. It had incredibly stupid writing most of the time and incredibly cheap production values -- sometimes it looked and sounded like it was shot in somebody's basement. And the second season was even more horrible in different ways. It would've been an embarrassment to have
Star Trek tied to such a train wreck.
Besides, I'm not sure how reconcilable the idea of a global alien invasion in 1953 -- and a renewed alien infiltration in 1988 -- could've been with Trek history. This is why crossovers between different SF series rarely seem feasible to me. It's easy enough to cross over things set in the "real" world, like, say,
Murder, She Wrote and
Magnum, P.I. or
Law & Order and
Homicide, but different SF shows almost always have incompatible future histories, cosmologies, and even laws of physics. Their distinctive worldbuilding is integral to their identities as franchises. So the only ways to do crossovers between them are either to do an "alternate universes" crossover or to do an imaginary story that just pretends they're in a compatible reality. The latter isn't desirable to me because I don't like how much it has to gloss over, and I'm not a fan of the former either, because alternate timelines should still have the same overall cosmology and physical laws, which is often not the case in different SF universes. (For instance, there would've been no sane way to cross
Star Trek, which is based on a somewhat accurate understanding of astronomy and the speed of light, with the original
Battlestar Galactica, which depicted a fleet somehow traveling between multiple galaxies in a single year while never going faster than lightspeed.)