How do these things even get in my pocket...

I just opened the washing machine after washing a load of jeans. In the bottom of the machine I found 51 cents in change, a green lighter (still works), and a bouncy ball. One, I don't smoke. Two, where did the bouncy ball come from? I'm sure neither of these things were in the machine when I put the load in, because I checked to make sure there was no spare change from my roommate's laundry. I have no idea what to make of this little incident; I might have to hire a detective.