Whenever I'd pk, I'd pretty much always do it for the "sport". It was pretty fun to just go around the wildy, finding some random person, and fighting until one of us wussed out.
I used to love my heart beating back in 2004-05 with my full mithril and addy longsword, which i was getting few days. I always ended up being killed and my armour was gone > minning coal again.