My kids wanted to use their Disney mugs for their water in bed, but if they tipped, they leak. Of course, I saw this as an opportunity to 3D print something. I found the very nice Coffee Cup holder that in_the_garage made and modified it to suit my purposes. I put a channel in the side for the handle to slide into and made two screw holes for mounting it. I printed them in glow in the dark plastic so that they can see them some at night.