If you are an advanced computer user with experience upgrading and building your own computers, you may be able to make some money on the side by taking in scrap computers. Once you have accumulated enough scrap equipment, you can use it to build working systems, or you can tear down those old computers and sell them for the value of the metal and plastic components they contain.
Take out ads in your local newspapers or online classified sections. Use the ads to ask computer owners for scrap equipment or to advertise your services as a computer recycling service. Many computer owners are anxious to get rid of their old equipment, so you may get an excellent response with just a few ads.
Gather all of the equipment that has been donated to you and separate it into working and nonworking components. You can test the status of the hard drives by using a USB hard drive enclosure--these devices transform an internal hard drive into an external one and allow you to attach those drives to the USB port on a working computer.
Use the working components you gather to build a full computer system. You can sell that finished computer system through a local classified ad or through an online auction service like eBay.
Contact the scrap dealers in your local area to determine the value of your nonworking components. The scrap value of computer equipment will vary according to a number of factors, including your local market conditions and the amount of precious metals like gold and platinum your particular components contain.