I plan to do a web service application by ASP.Net, but I don't know What kind of ASP.Net application will be probably popular.I konw that the social bookmark (such as http://www.furl.net/index.jsp) is very popular, and that web service application is very good.I don't think my web service application for social bookmark can exceed http://www.furl.net/.So I hope to do some other ASP.Net web service application, any ideas for me? Thanks!