You can keep them right in your fridge in their Leech Mobile Home! Yeah peoples, it's soooo much more fun than those boring ant farms or bug jars!
I've actually had leeches on me, fortunately I was able to shake them off before I got bitten. One of them attached itself in an upright position to the wooden floor with his sucker and stayed there all nice an' upright till everybody got up to leave the room after a presentation, and then when it felt the vibes of people nearby it started flailing its body around wildly to find a host, with its sucker still stuck to the floor.
yes, my ew-meter was set off.