Biology fact: the testicles didn't descend because sperm couldn't be kept inside the body due to temperature, that's just the reason why they haven't gone back up. In actuality, testicles are on display for women to take a look at for the purposes of assessing their mating potential. Now of course, balls can be fun, and if you're like me and enjoy a good pair, how about you come on over to /r/Balls and join others that are pretty damn keen for the same thing?
The user community here is very small with just over 3,000 people being subscribed. It has been around for 6 years and as the name suggests, it has but one focus: balls. You're going to see big ones, hairy ones, black ones and a whole bunch of others. Hell, there's even a submission of a dude that has three testicles! How fucking cool is that?
For a sense of update frequency, there have been 35 new submissions in the last 7 days. Not bad by any stretch of the imagination!