He used to drop into my chambers once in a while to smoke, and was first-rate company. When I gave a dinner there was generally a cover laid for him. I liked the man for his own sake, and even had he promised to turn out a celebrity it would have had no weight with me.
The owners manual on every vehicle should state how often the manufacturer recommends that you tune up cars, but as a general rule it is every two years or 30,000 miles, whichever comes first. Driving under extreme temperature and weather conditions will make parts wear out faster, however.
How often you tune up your computer is largely a matter of preference. Some people do it daily or monthly, while others take a more random approach. In most cases, you should probably tune up at least once every three months, but once a month or once a week is probably better.