Wow, that's a wave of nostalgia hitting me! NOLF was also one of the funniest shooters I've ever played.
The effects for the dis-integrator pistols on the spaceship were so simple yet so classic. It's one of the early games where you got to do lots of different fun things, like scuba diving with a spear gun, driving a snow mobile, etc rather than smashing crates in a bunker.
I think it was the sequel, but I'll never forget the chase sequence, at breakneck speed through Marrakesh(?), involving deadly mimes on tricycles.