Rating Bot is a simpel robot which helps with creating voting in best Web 2.0 style where you can vote on each blip. The robot is made by Przemysław Gajda.
You can add the robot using the address: firstname.lastname@example.org
An example on where the robot has been used is on the picture bellow.
The idea of being able to rate each blip is rather smart. It will make it to vote for ideas described in a full blip. So this links a lot to the polling gadget from yesterday. It does thou vote for different blips. So this will be use full when you have more to choose from.
It is possible for a person only to cast one vote for each blip. The way this has been implemented is by using annotation to store each persons vote. I have always used the Cache storage for handling metadata and then linked it to the wave or blip. But using annotations can make it easier to persist data. Then everything is stored in just one place. It would also be possible for other robots to interact with the data created.
You can have a look at the Java code behind the gadget at code.google.com. I could learn a little from the way this code is structured.