TOO LATE for Christmas but just in time for New Year's comes a breakthrough in the age-old problem of how to attend a party without actually going to it.

Our president has shown us the way. We learn from a riveting dispatch by Donnie Radcliffe in The Washington Post that instead of a "drop by" at the Washington Press Club's congressional dinner on Jan. 26, he offered his celluloid presence, via videotape.

This is frontier stuff -- the social equivalent of Barney Clark's artificial heart. The club declined. The bill for last year's three-minute filmed "drop by" came to $2,000.

That's their business. I am thinking of what this new technique could mean to the rest of us. Who would not gladly pay $2,000 to avoid driving to Virginia on New Year's Eve and finding an address on North 29th Street -- "You can't miss it, just drive by four churches and angle left by the overpass."

Of course, you or I might receive some resistance from a host or hostess on paying the production costs of the taped you. Don't quibble. Think of the savings in physical terms. No busses from boors, no dagger-heels driven into your instep, no bruises from buffet-line scrimmages, no being nailed to the wall by someone who wants to talk about the Mexican default problem.

The protocol of the absent presence is intriguing. The president's men asked the Press Club for a script. You could do the same with someone who asked you to a dinner you want to half-skip. What Washington hostess could resist having guests programed to say just what she wants?

Once you receive the invitation, offer the "message option." Once the price and content have been negotiated, call up your hairdresser, press your best dress, lasso a free-lance television producer and arrange a filming in the comfort of your own home.

Unless your hostess has special needs -- and we'll get to that later -- I would suggest a one-size-fits-all natter based on Washington conversation as you know it at what passes for revelry in the Nation's Capitol.

Open with your views about whether Ronald Reagan will run again. If you were there, you would surely be asked, and it is bad manners to say, "I don't know."

Segue into your evaluation of Democratic candidates in order of your preference, if you have one, and at the moment, it is okay, even chic, not to. Throw in your version of the "real" reason that Teddy withdrew -- remember, nobody can argue with you when you are on a cassette.

Murmur something about changes in the White House staff. Say the reason that you're not live is because Mike Deaver sent you the proofs of his diet book, and you're eating tofu. Mention that you've heard -- simper that you just can't tell where -- that Baker can't stand Meese, and you're pretty sure it's Jim, not Howard.

Senate Majority Leader Baker is a hot topic. The lame-duck session laid waste to many yuletide parties, and the word "hostage" is currently as feelingly spoken as during the Iranian crisis. "I think they were holding the MX hostage to the gas tax, don't you?" you might observe to the people who have gathered around the machine to receive the message option.

But, as I say, your hostess must be your guide. She may need a listener, a virtually extinct breed hereabouts, and might pay double to have you on camera, smiling and nodding, and saying at intervals, "I never thought of that" or "How well put." That's unheard of at a serious Washington affair -- and there is, alack, no other.

Or possibly, although it is not likely, she is short a bore, an essential, unifying figure at any party.

Offer your room-emptying monologue.

"Isn't that senator from Oklahoma, Wilson, just wonderful, the one who told Jesse Helms he was "obnoxious"? Oh, his name is Simpson, you may be right, and I guess he may come from Wyoming. I sometimes get names wrong. I was saying to Harry just the other night, Wednesday -- what am I saying, it was Thursday, I remember now because I went to the airport to pick up Sissy, you know she worked for Reagan in Tallahassee and she's president of the YRs at her school. I liked to die when I saw her. She had on satin knickers. Do you like knickers? Do you think I could wear them? Harry says my legs are really not that bad and . . ."

You get the picture. Your hostess will go for it.

You, while it is being played, can be home by your fireside in your bathrobe, sipping brandy if you like -- no "sobriety checkpoints" to fear in darkest Virginia. You greet the New Year with the smile of one who has discovered the joys of electronic socializing.