mid - This extension indicates a sound file created with a Musical Instrument Digital Interface. Windows Media Player will open and run these files, however they don't sound like normal .wav or .mp3 files (described later). .Mid files are designed to product synthetic sounds using a computer's sound card. ) will ultimately determine how often you'll need to de-dust your machine. But as an average, you shouldn't need to perform this procedure any more than once or twice a year. The entire exercise should take no more than twenty minutes tops and once complete, you'll immediately see and hear the difference in your machine. The commands in a program are pretty useless unless they have some data to act on so programmers either give the programs some data to work with (list of names or numbers for example) or they make the program generate it's own data. Sometimes, the data comes from an outside source like the Internet or the computer that the program runs on. But once the decision to buy a computer is set in stone, what can be done with the old one? There are alternatives to selling a computer and this article is going to introduce a few of them. 1. Give it to the kids. This is of course, assuming the kids are too young to whine about not having enough SDRAM or less than a 160GB hard drive. The easiest and cheapest method uses an Ethernet connection, which requires a series of network cards, a cable for each computer, and a router. The network card is similar to the old modems we used in the past to connect to the Internet, however in a home network, it's used to communicate with every computer that's connected to it. But it certainly hasn't stopped there. In the not too distant past, Netscape converted its once commercial version of its Navigator web browser to open source. And today, open source is venturing into the commercial realm as well. At first thought, the idea of open source may sound just plain crazy to those who earn a living from software development.