Here are some things to consider:
1. Money is made by charging businesses to not only take the equipment away, but take it away and dispose of it in an environmentally safe way.
2. The other aspect, in particular regards to digital information on computers, is to ensure you dispose of the information properly and provide proof/certification of its disposal.
3. You might also want to provide a portal of information for companies and consumers. Keep in mind that Dell, HP, Lenovo, and Gateway all have recycling programs from free to fee-based, so you have some pretty stiff competition.
4. There are many options available, but consider leveraging information. For example, if a company has 100 Dell computers, help them access Dell's website and serve as a liaison to Dell or work between customers and Dell's website to arrange for the computer disposal. You could then charge a nominal fee for this service and have to do very little work or capital investment yourself.