The Service Employees International Union (SEIU) is staging an online contest with a $100,000 grand prize to foster public dialogue and build a constituency for economic reform.

As the web site title suggests, the union seeks to reward a great idea, the best Since Sliced Bread . Entries must be 175 words or less and explain what the issue or problem is, how the contestant would fix it, and how that would benefit working men and women in the United States.

The winner will be selected by expert judges and site registrants in five rounds of vetting and voting. Submissions (over 1400 in the first week of operation) are searchable by keyword, and the entries garnering the most discussion are featured on an “Explore Ideas” page. The fifth “Most Active” idea listed today was “Stop whining.”

This appears to be the first attempt by a major American political organization to use the lure of a cash prize as a means of online civic engagement.