Anyone else have a sudden flashback to The Great Mouse Detective when they see a rodent operating a bell? And I will not be eaten by a cat summoned by a mouse. DO YOU HEAR ME? I will not got out that way!
In all seriousness, this is Little Grisu of Mouse Agility using the doorbell that he's been trained to use to get inside. Visit Mouse Agility to see mice do more tricks than just about any pet can.
[via Laughing Squid]