flux capacitor -- Just a term, and acceptable without science. because it was a comedy (Space Opera, except time travel)
dilithium crystals -- We already use lithium for energy, so TOS was ahead of the curve with this. Gene Roddenberry was interested in having plausible science, if not possible. In TNG they've moved up to trilithium crystals.
I have long held a theory that the reason that everyone in TNG is so laid back is because the lithium leaks out of the engines and bonds withtheir blood, and so they all are on lithium.... *g*
Where is Mobius Drive from? I can't place it off hand. Maybe it is just named after a guy named Mobius?