Mine would be bugs. It started with my Khajiit characters cause you know their cats and cats like to chase small things
But then I found that you don't need to chase the bugs down, if you're a good enough shot with a bow you can pick em off. Now EVERY character that I make ends up bug hunting
Another one, same as you Arnathorn. I tend to keep every note / journal I happen across. Mostly it's because I want to keep the memory that the note/journal finding situation made. For example.....Up around the mountains of Markarth ( I believe ) there is a little camp with a cave bare guarding the camp along with 2 corpses. If you kill the bear and snoop around you will find a note and a journal detailing the becomings of the pair, they where a young couple in love and because of the of the disapproval of the parents involved they decided to make a life of their own.
Now if you put 2 & 2 together you can figure that the bear was attracted by the smell of the camp fire one night and the young lovers died defending the camp. This is why I tend to keep those notes and journals, to keep the memory of those who died alive. At least I will remember them..... 