I just read an article on the many uses of old computers. The best ideas seemed to be ways to allow your computer to be used by others over the net. One obvious use is to let the old computer serve up torrent files. Even a lanky old Pentium came server this purpose.
Another noble use for your old PC is to have is join the TOR network. This essentially allows users to hide their location and identity. It makes it harder for somebody to track their internet traffic. The goal of this system is to provide personal freedom. The software is open source. It is good for IRC, Instant Messaging, and web browsing.
Finally you can install the BOINC client on your computer. It lets you choose worthy projects for your computer to work on during idle processing. For example, you can help the search for extra terrestials by choosing the SETI project. If your old computer has a graphics processing unit (GPU), it will help the effort even more. Now there is no need to junk that old PC. Put it to good use.
Struggling With the Calendar Code - Turns out we need to work all weekend on fixing bugs before the customer will even consider accepting our system for production use. I got assigned a tick...