Recently I found out about http://dailyshoot.com/. Before that I found out about http://www.crossfit.com/. What other sites do you know of that give you a very specific tasks to do everyday? Or every week? I find that I am more motivated to learn something when I am given specific tasks to do or projects to work on so services like this are a big help. Looking for any and all things so don't hold back.
I'm looking for "____ of the day/week/month" sites that are not the typical word or quotation of the day sites. Something that could really get me thinking. Please recommend your favorites.