I consider my computer a necessity....not a luxury. I use it to work, play, and communicate.
Like most people, mine isn't the latest and greatest, and I have an older model stashed away. I gave another older model a new lease on life with Linux.
My living room PC is solid, works wonderfully, and is very dated. However, it works just as fast as my office PC thanks to Ubuntu.
What is Ubuntu? It's a variety of Linux....a free operating system developed by the open source community. It's easy to install and configure (it does the work for you in 99% of the cases), runs quickly, and breathes life into an older machine quite well.
I use my Ubuntu box as a multimedia machine. I have a cable running from it to my television and my stereo system. This way, I can download music and play it through the stereo. I can watch TV on Hulu and Youtube, and sit on the couch and chat with friends and family. I can sync my ipod and mp3 players (you still need Itunes to restore an ipod), and I can watch movies stored on my external HD.
Ubuntu is VERY user friendly, and there's a ton of online support in addition to several great, reasonably priced books. Just Google "Ubuntu" for more information. It can also be set up as a file or print server and even comes with OpenOffice.org, an office suite that is very compatible with MS Office.
Why let that computer gather dust? Give it a new breath of life and see what it can do!