WORTH NOTING ON TV

* FRIDAY Coneheads Conquest Countdown (MTV, 7-8 p.m.): Among the weirder - and more popular - sketches in the NBC "Saturday Night Live" repertoire have been the ones starring those space aliens called "Coneheads" - you know, the pointy-headed creatures named Beldar and Prymaat who look suspiciously like Dan Aykroyd and Jane Curtin. Stuck on Earth, they are forced to assimilate, and by now they are assimilated enough to find themselves hosts of their own TV special with a comedy-music format.

Besides playing their bizarre roles and introducing their top-10 choices of music videos, Aykroyd and Curtin bring on special guests Michael Richards of NBC's "Seinfeld" and model Cindy Crawford. The occasion is also a good excuse for them to screen clips from their Paramount film "Coneheads," to be released next week, in which the aliens encounter suburbia. * SATURDAY National Press Club (C-Span, 6-7 p.m., E.T.): The guest speaker is Donna Shalala, secretary of health and human services. Naked Sports: Four Portraits (Showtime, 10-11:15 p.m.): The "naked" portraits in this case are of sports, not people, despite a title that sounds as if hidden cameras had been put in locker rooms. The documentary examines the pressure, deals, and other forces dominating a business that generates some $25 billion a year.

Related aspects of sports are examined from four standpoints: a star player, a promoter, a franchise, and an owner. Michael Jordan - a businessman who often has to fend off efforts to exploit his huge fame - is the first subject. The program also looks at boxing through the career of a leading promoter - Dan Duva. The franchise is the Dallas Cowboys, with their win-at-all-costs approach. And the spotlight also falls on Cincinnati Reds owner Marge Schott, currently sitting out a one-year suspension for al leged racial slurs.

Please check local listings for these programs.