The U.S. government may not be an anachronism, but the people in charge of it sure are. Nations all over the world look to our style of government for a model because it is indeed an excellent way of running a nation, large or small. Provided, of course, the people in office are in some sort of touch with reality.
Term limits are the perfect solution.
After two or so terms, you really cannot expect a senator to know what's going on in the world around him. A new face every 12 years certainly would keep an influx of fresh faces and ideas in our government. The people elected to represent us would be people who could serve that function - not some ancient, venerable politician who is so pampered, feeble and out of touch with the times that he thinks software is a sexy undergarment. The above statement, by the way, is case in point with the example of Sen. Strom Thurman, the doddering old twit who has been in office twice as long as most students at UF have been alive. It must be a running joke to see how old of a senator they can keep in office.