As you know, tribbles have the pesky habit of mating constantly and reproducing at alarming rates. We had an entire office filled with tribbles from floor to ceiling and we needed to do something before the walls exploded from the furry pressure.
It turns out, if you attach two Tribbles to a pair of slippers in exactly the right orientation, they are totally happy and lose all desire to reproduce. (How we came to that conclusion is a long, long story probably not suitable for human consumption.)
Anyhoo, our loss (of tribbles) is your gain (of Tribble Slippers)! With every step, your Tribble Slippers will purr happily.