As hundreds of savings and loans sink in a sea of red ink nationwide - a disaster that could cost taxpayers $100 billion to rescue depositors - some financial sharks are swimming in those same waters.

The wheelers and dealers are acquiring dead and dying savings and loan institutions in packages worked out with the FSLIC, the federal insurance fund that guarantees deposits.Why would the shrewd money experts be fishing in such troubled seas? The reasons are simple: the possibility of making a profit at little risk. And if it doesn't work out, the taxpayers pick up the wreckage.

Frequently, the buyers of failing S&Ls put up little money, the FSLIC puts in some federal funds, the agency agrees to cover any future losses of loans already on the books, and the buyer gets a tax write-off from the already-beleaguered U.S. Treasury.

What happens is that buyers may not pump enough cash into dying S&Ls to revive them. In the meantime, they get a big tax break, and if the institution fails, the government, not the buyer is left with the debts.

For example, a Texas company recently acquired 13 Texas S&Ls with assets worth $2.7 billion, for a mere $48 million - 1 percent of the liabilities of the firms. The FSLIC put in nearly $500 million of federal money and guaranteed future loan losses.

As one congressman put it, the deals work out to situations where any potential profit is privatized, while potential losses are socialized. No wonder the financial wizards are interested.

Yet it is hard to fault the FSLIC. The agency is trying hard to find buyers for S&Ls as a way of keeping federal funds from having to pay off totally bankrupt institutions. If the deals are greatly to the buyer's advantage, well, the FSLIC has little choice. The agency is nearly bankrupt and is trying to buy time until a new Congress comes up with some answers.

In some cases, the mergers or buyouts offer advantages. If they work, then the FSLIC is that much farther ahead. But they may end up costing the taxpayer even more money when they don't work.

The S&L crisis must be dealt with quickly by the new Congress in 1989 and allow the FSLIC to get rid of the bargain-basement, crap-shooting atmosphere that surrounds attempts to rescue collapsing S&Ls.