...
- res_com.ogg – generic research / technology
- res_droid.ogg – droid research
- res_pow.ogg – power research
- res_struttech.ogg – structure construction (a factory with modules being added)
- res_systech.ogg – systems research (a sensor being designed/used)
- res_weapons.ogg – weapons research (some sort of cannon turret)
I've also seen blank versions of these videos - not sure if that's a recent change or not?
They are incredibly useful when creating custom cinematics or cutscenes because they don't contain any audio.