There is large market demand for hand-painted greeting cards and post cards. If you have the ability to produce the finished product yourself, that's great. If not, there are many artists who will be glad to assist you, for a fee. The greeting and post cards can be wholesaled to retailers or sold directly to companies to give as corporate gifts to clients. If you plan to specialize in hand-painted post cards, you'll want to sell them in high-traffic tourist areas like airports, tourist attractions and beaches. Whichever you decide, this business can be both fun and profitable, and best of all, it can be started for peanuts.