The writer contracts with businesses or nonprofits to create press material, brochures, ad copy, and features for and about the organization. If you have a health background, you might do press material for small medical groups or features for hospitals. Ghostwriting is similar to the above. They look for ghosts to write for them under their name. It is not difficult to find people in the business world who will pay you to be their ghost.
Grant writing is another opportunity for the part-time writer.
Many organizations seek grant money and need well-written proposals. This skill is easily learned and most proposals are short. Some writers work on a contingency plan wherein the writer gets a larger fee if the organization wins the grant. The individual who has a lifetime of skills and has organized them around a number of topics will find that many areas of the writing business are available to him or her. It is difficult to support oneself soley by writing.