They're part of our collective TV unconscious: the mewling kitty after the Mary Tyler Moore Show (MTM Enterprises' spoof of the MGM lion), the ''Sit, Ubu, sit. Good dog'' at the end of Family Ties (in honor of producer Gary David Goldberg's dog), and the ''...and dance by the light of the moon'' ditty that closed every episode of thirtysomething (the producers' tribute to It's a Wonderful Life). While they last only a few seconds, these production-company logos are occasionally more noteworthy than the programs. Here are some current examples probably jockeying for space in the recesses of your brain:
Hudson Street, Katie Face Productions. Action: An invisible hand (belonging to star and exec producer Tony Danza) signs the name. What It Means: When Danza first saw his daughter, now 8, ''she had this incredible little face, and I had no way of describing it other than to say it was a Katie face!'' he gushes. ''The logo is also an homage to my upbringing in parochial schools, where they stressed penmanship.''
The X-Files, Ten Thirteen Productions. Audio: A boy's voice says, ''I made this...'' What It Means: ''Ten and thirteen are lucky numbers for me,'' says exec producer Chris Carter, who was born on Oct. 13. The voice is that of Nathan Couturier, then 9, son of the supervising sound editor. ''We're all just sort of big kids making mud pies,'' explains Carter.
The Drew Carey Show, Mohawk Productions. Audio: A child's laugh. What It Means: ''My wife is six feet tall with a dark black Mohawk,'' explains exec producer Bruce Helford. The giggle and sonogram are courtesy of his son, Aven, now 2, because ''when I create a show it's like giving birth. A lot of people think it's like a pro-life statement, which it wasn't intended to be.'' Rejected Ideas: ''We thought about using things that had to do with Mohawk Indians, but those didn't seem as personal.''
Space: Above and Beyond, Hard Eight Pictures Inc. Audio: A voice says, ''Watch your hands!'' What It Means: The phrase refers to a croupier's warning about dice hitting any player's fingers. Hard eight ''means two fours,'' says Glen Morgan, who is an exec producer with James Wong. ''Jim and I love playing craps, and it also made a statement that we like to gamble on thingsnot that we should go to Gamblers Anonymous or anything.'' Rejected Ideas: ''We didn't want to have a croupier going 'Winner, winner, winner,' because then the show could stink and everyone would make fun of us.''
The Single Guy, Hall of Production. Action: Dark clouds clear away, revealing a lithograph. What It Means: ''Hours and hours of hard work,'' jokes exec producer Brad Hall, who found the drawing in an art book. ''It has a kind of workingman's feel.'' Rejected Ideas: ''I thought that since I have such a stupid name that happens to be a noun, I should use it, but 'Hall of Horrors' sounded kind of silly.''
Jag, Belisarius Productions. Action: Wind blows sand off the engraved name. What It Means: ''Belisarius was a general back in Roman times,'' says exec producer Don Bellisario. Rejected Ideas: ''While I have a great ego, I couldn't bring myself to name my company after me, so I took it one step removed and named it after my ancestors. I consider myself a filmmaker, so maybe I should have named it Cinemus or something.''