As a doctoral student I had my own office on the top floor of the Psychology building.  It also served as part of my research space, and in adjacent rooms I housed the wild house mice and deer mice that I had trapped in the field, and their lab-born descendants.  By the time I finished up my degree, I had taken over much of the top floor -- as soon as a room became vacant, I moved some of my wild mice into it.  The behavior geneticists, also on that floor, were so afraid of my wild mice's genes contaminating their fake mouse gene pools, that they would just abandon those rooms.

    One morning I arrived at my office and discovered that some of the loose mice had built a nest inside my typewriter.  Mice glue their nests together with urine, which is a very effective glue.  Their urine had been spread all over the innards of my typewriter, sticking the moving parts in place.  I spend the whole morning using solvents to remove the urine glue.  Then I put my typewriter on a piano stool in the middle of my office, hoping the mice would not find it there.  I went home for lunch.  When I got back that afternoon, I found that the varmints had rebuilt the nest.  I was enraged.  I grabbed a 2 x 4 from one of my research rooms and started swatting loose mice.  In the process, I had to move heavy book shelves and other furniture to expose the varmints, and then swat them dead.  I went from room to room, swatting the varmints.  After I could find no more, the adrenaline rush abated.  After a break, I tried to move the furniture back, but without the adrenaline rush I could not move them, I had to get help to get the furniture back in place.