In the search for new business models for community news sites, many experimental advertising platforms have been used. MinnPost has its Real-Time ads widget. Printcasting is trying out MediaBids. And Spot.us is planning something called Community-Centered Ads, where people could view an ad or fill out an advertiser’s survey in exchange for credits they can use to pay for original reporting. So here’s a question to Idea Lab bloggers and readers: What other experiments have you seen in local sites running advertising that’s beyond the norm? What is working and what has failed? Share your thoughts and observations in the comments below, and hopefully sharing intelligence will help all involved.