Nothing better than a cost-benefit analysis.

Get a piece a paper draw a line down the middle, put the costs on one side and the benefits on the other, ease of start-up etc.

Pick 3 ideas and research and rank them looking up past small business articles in magazines. They all have best start-ups for 2008.
Look at your state business government site, what businesses are needed in your state and in your city, what are people demanding currently?

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