One type of work you can do entirely from home is word-processing. And potential clients are everywhere, from the small business across town that needs an extra hand, to the college students next door trying to finish their mid-term papers. If you really enjoy this type of work, you can also become certified as a court reporter or medical transcriptionist to increase your client base. While much of this work requires being in the courtroom or the doctors' offices, an increasing number of these professionals are working from home-based offices. A computer, e-mail account, typing skills and a solid background in writing and grammar.
Certification is necessary to be a court reporter or medical transcriptionist.
And you can do either type of care in your own home or at others' residences. One niche to consider is care for sick kids. This creates a big need for a service that provides occasional daycare for sick children. Pet care can be as simple as walking and feeding a client's dog once a day. If you have a yard, you can host the pets yourself.