Here's a great approach along those lines (i.e., research an idea among prospective clients before investing a lot of time building it): http://www.amazon.com/F

Here's a great approach along those lines (i.e., research an idea among prospective clients before investing a lot of time building it): http://www.amazon.com/Four-Steps-Epiphany-Steven-Blank/dp/0976470705 http://www.amazon.com/Four-Steps-Epiphany-Steven-Blank/dp/09...