Some of my favorite riffs are the ones based on TV theme songs. I don’t mean incidental music or random songs from a TV show, but the beginning or ending theme.
One that comes to mind is whenever you’d see someone through a windshield, particularly a woman or someone driving a white car, they’d sing “How will you make it on your own?” from the Mary Tyler Moore Show.
One of my fave recurring gags is how an exterior shot of a tall building (most often an apartment of some kind) will prompt the gang to break out with the theme song from The Bob Newhart Show. It’s without lyrics, aye, but the gang vocalizing the instrumental track? Wonderful.
I think, they used to do this incidental music from My Three Sons on occasion, when you’d get an establishing shot from outside the house. At least that’s where my mind went when they’d do it, but it could have come from any TV sit-com. But, like this, for instance. I believe they did this…
Of course, I can’t remember a specific episode to confirm that.
I don’t remember the incidental music from My Three Sons popping up (that could just be my faulty memory at play here), but I remember a “My Three Skulls” riff in Eegah prompting a vocalization of the theme song.
I love any time they reference the Greatest American Hero theme song. My brother and I used to watch that show all the time at our grandma’s house, and the first time I heard the riff with the theme song in Star Crash is the first time I first decided MST3K would be my favorite show forever.