Tanks, sure. Social security - that's obvious. But Indian-built jewel bearings? Bamboo research? A 34-meter antenna in Madrid, Spain? Besides the well-known, big-ticket items, US tax dollars pay for some pretty obscure things. Lurking within the massive 1985 budget appendix are hundreds of little line items undreamed of by even the most imaginative taxpayer.
The State Department, for instance, contributes $15,000 a year to the International Office of the Vine and Wine. The Office of Personnel Management is still paying pensions to 71 people (or their widows) who worked on the Panama Canal. Just under a million dollars of the defense budget goes toward the National Board for the Promotion of Rifle Practice.
The money spent on these projects is pocket change compared to the billions earmarked for food stamps, F-16s, or interest on the national debt.
Still, they give a vivid picture of government spending that a dry figure labeled ''defense spending'' can't match.
Take the William Langer Jewel Bearing Plant in Rolla, N.D. Built for the Defense Department in 1957, it churns out some 2 million ruby and sapphire bearings a year, for use in such precision devices as chronometers and navigational devices.
It is the only place in the United States where such bearings are built, points out a General Services Administration official, and is thus necessary for national security.
''The manufacture of these things is something of an art,'' says GSA contract officer Jerome Consiglio. ''By the way, better than half the employees up there are Chippewa Indians. Acute eye power is needed for the work, and apparently Chippewas have pretty good eyes.''
On the other hand, nobody is saying that bamboo research is critical for national defense. In fact, it appears that bamboo research isn't really critical for anything, except maybe Giant Pandas.
''Yes, there is a Bamboo Research Station,'' says Bruce Schwartz, a spokesman for the Department of Agriculture Research Service. ''Sixty-six acres. Ten miles south of Savannah, Ga., on US Route 17.''
Mr. Schwartz adds, however, that the federal government is not too wild about the place, and has in fact been trying to give it to the University of Georgia.
Overall, research on plant production is projected to cost the US $191 million in 1985. The Department of Agriculture will also spend $116 million for price supports for wool and mohair, and $415,000 for sunflower crop insurance.
At least all those crops are grown in the US. The new, 34-meter antenna that would be authorized by the '85 budget is slated for Madrid, Spain.
The antenna, which can't cost more than $750,000, is for the National Aeronautics and Space Administration. (''We've got a tracking station there,'' huffs a NASA official, when asked why US money is being spent in Spain.) It will be used to track Voyager, Neptune, Galileo, and other coming US space projects.
Among other coming unusual expenses for the goverment:
* Purchase of flowers for American battle monuments ($24,000 from a trust fund of private contributions).
* Auctioneer and broker fees for selling off government property ($2.4 million).
* The 1985 presidential inaugural ($2.3 million, under the ''District of Columbia'' fund).
Finally, the budget appendix, which is itself so large it could almost be laminated and used as a coffee table, is sprinkled with statistics that illustrate the vastness of the US government.
In 1985, for instance, records in the National Archives and federal records centers will total 16.3 million cubic feet. Four million pages of secret documents will be reviewed for declassification.
GSA government motor-pool vehicles are expected to travel 972 million miles next year. US attorneys will spend 796,000 hours in court.
And then there is every tourist's favorite Washington experience - the US mint. The Bureau of the Mint will manufacture 14 billion pennies, 1.6 billion dimes, and 1.5 billion quarters next year.
A penny, by the way, actually costs 1.53 cents to make.