Running

I'm a b-ball player, hiker, and a pretty active guy. I've done the free-ball thing but my balls are huge and the doctor has advised me against this. I now use compression shorts or swim jammers so that I don't end up visiting the doc because they get really sore bouncing around.
 
I like running too but never go for freeballing (unless you call wearing no underwear under a running tight "freeballing" :D
I generally don't like it when it swings from left to right and back during a 10 or 15k run