Hey, I know UFO! And "Terror from the Deep"! Fun games indeed! I always wished someone would turn these into a round-based multiplayer game. It could have been a nice and simple, yet very interesting and exciting strategy game. Kind of an isometric, round-based counter-strike, haha...
I remember that I liked those hightech weapons where you could set various waypoints in order to shoot someone or something: down the corridor, out through the window, one storey up, in through the balcony door and KABOOM! Har, har! 8D