OMG!! I feel for you! We have been fighting with a mouse (mice) for a while now. Like one of the above posters said, the mouse would eat the food out of the traps and keep going. Drove us nuts! Finally, reluctantly, I agreed to put poison out (very carefully of course!).
I walked into my laundry room today, looked down as I had one foot in the air, and realized I was about to step on a DEAD MOUSE!! EWWWWWWW!!! I screamed and got out of there so fast you would think it was still alive. I still shudder thinking what if I had stepped on it!