Richard Russell provides a list of twelve characteristics of the "ideal" business, most of which I've considered intuitively but could not have written and encapsulated as consisely as Mr. Russell has. Cutting out all the valuable explanations in the article:
(1) The ideal business sells the world, rather than a single neighborhood or even a single city or state.(2) The ideal business offers a product which enjoys an "inelastic" demand.
(3) The ideal business sells a product which cannot be easily substituted or copied.
(4) The ideal business has minimal labor requirements (the fewer personnel, the better).
(5) The ideal business enjoys low overhead.
(6) The ideal business does not require big cash outlays or major investments in equipment.
(7) The ideal business enjoys cash billings.
(8) The ideal business is relatively free of all kinds of government and industry regulations and strictures.
(9) The ideal business is portable or easily moveable.
(10) Here's a crucial one that's often overlooked; the ideal business satisfies your intellectual (and often emotional) needs.
(11) The ideal business leaves you with free time.
(12) Super-important: the ideal business is one in which your income is not limited by your personal output (lawyers and doctors have this problem).
These factors all focus on demand, profitability, and personal satisfaction. But what about supply? Any business that came close to meeting these would be buried by competition. For example, working as a rock star or famous actor would satisfy nearly all of these, yet those aren't particularly appealing lines of work.
The ideal business must have a unique competitive advantage that discourages others from entering the market. Without that, the rest hardly matters.
The ideal business doesn't have to stock products, manage inventory, track distributed resources, or finance its customers' purchases.
The ideal business, it would appear, sells cheap, one-play-only, self-destructing CDs and DVDs loaded with popular movies or video games. Said CDs and DVDs are made at the cash register, by an easily instructed, entirely automated system that requires human intervention only to load it with a fresh batch of blank media.
It sounds like blogging for $$$ would meet all those requirements
And so it seems that the "ideal business" is to conservatives what "peaceful utopia" is to liberals; a pipe dream.
Blogging fits, but the competition makes it hard to make money, as FWP noted.
One business I've considered getting into is buying/leasing some of those picture printing stations like you'll see in Kinko's. People put in a credit card, print, and go. Most can negotiate geographic monopolies.