When developers launch a new software or website they often do a Beta test. A beta test is a live launch of the product that you allow people to try and help you find any bugs. Sometimes these tests are open to the public, other times they are only available to invited participants.
When I launched marketingenious University I had a Beta group of 40 students test it out. I had a forum set up for people to post feedback and I made a lot of changes based on responses. Beta tests are a great way to get some feedback before launching the full blown product or spending a ton on advertising.
What could you Beta test?