Stargate SG-1 and Stargate Atlantis were often very funny.
"You go, Yu."
"I hope you enjoy the shot...of my ass."
"Man, you guys are a loong way from Oakland."
Eureka, W13, Farscape, Sanctuary, Dr. Who, Firefly, Misfits-the list goes on of scifi with humor. Not all of it is funny-but a lot of shows incorporated humor in their delivery.