About once a week I would visit Plinky and peruse through their prompts and answer the ones that caught my fancy. They kept their site open but their last new prompt was in April (2010). I discovered Automattic, the creators of WordPress, acquired Plinky just last week.
If you are not familiar with Plinky, it is a site that provides daily prompts, usually in the form of a question. You can answer with words, maps, playlists, pictures, you can see what others have answered and you can also have your posts automatically post onto other sites like wordpress and facebook.
WordPress believes Plinky is great for those days when you want to write, but are hitting a mental wall. Think of it as an idea generator to fuel your creative mojo.
I have almost 60 plinky posts on my blog (link). Or here are a few that I have answered.