Because UB40 appears on soundtrack
The box for Night Trap can be seen a few times in Zeke's office. Like Sliver, it also heavily features hidden cameras.
Servo mentions the film by name.
It is mentioned on the cover of an issue of Empire magazine.
Mr. Burns puts hidden cameras in everyone's homes and says "I got the idea from that movie Sliver"
When the women become unruly during a movie marathon, Jason says, "I knew we should have stopped after 'Sliver.'"
Eugene says he dressed Louis up to look like Billy Baldwin in Sliver.
Mentioned in dialogue
Mentioned by Karl
discussing the works of Sharon Stone
playing on TV in Carly's apartment
Lisa is spying on people with CCTV cameras planted in their houses.