My Dad said that the one time his family had a mouse, his dad caught it using a bucket with a set of book stairs and a ruler balanced across the top with food at the end. So I set one up and twice the mouse got the food without falling in because mice are unbelievably light. Tonight though I heard the mouse again so I set up the paint stirrer with a cracker and a few minutes later a mouse came onto the paint stick and fell into the bucket.
It almost jumped out, too, even though it is so tiny. It took a running start around the bottom of the paint can and tried to jump out. But the paint can is about 2 inches too deep. If you try this, get a really deep bucket, because this mouse is smaller than pet store mice, I bet a proper sized one could get out. Anyway, I put a book on top of the can with a tiiiny air gap and it has the cracker and everything.
And even though I have not even outsmarted it, as I just copied my grandpa's idea, and mice have probably an IQ of 1 or 2, I feel smart. (I tried to take its picture but the flash was too powerful for the paint can, I think. )