Any provides a super easy way to get a random model instance from an Active Record model.. This is really handy when testing or populating your database with dummy data.
Say you have a model named Post and you want a random instance of it, all you have to do is:
Post.any
If you don't have any posts, it will return nil instead.
Due to the awesomeness of Rails 3, you can chain it to stuff like:
User.where("username != 'sam'").any
That would give you one random user who's username isn't sam. Pretty handy stuff.