I took everyone's advice and got all kinds of different traps and put them around the apartment. So last night (Around 11:30) I am in the living room watching TV, the dog starts acting strange. She keeps on trying to get under the computer table and trying to dig into the printer. I moved the table-nothing, I look under the table- nothing, looked behind the printer -nothing. This went on for about 20 minutes. So then I decided to move the printer and a mouse ran out of the printer. I yelled, tried stepping on it as I am chasing into kitchen, while the dog is chasing it too. We were tripping over each other. It was a sight to see. I must have a ninja mouse living in our apartment.