I started editing Wikipedia during the Christmas holidays of 2011 because I noticed that Bus routes in Newcastle, New South Wales was just a company page about one of the two main bus companies in Newcastle, and didn't mention the other company at all. So I made an account, started fixing it up, and learning the system as I went. Then my tendency to throw my self into anything I start doing to ridiculous lengths kicked in, I discovered the arts of stub sorting, fixing dablinks, and adding infoboxes and navboxes, and within a few days had over 1000 minor edits. I haven't really slowed down much, but presumably the novelty will wear off within a few years.
Mostly I stub sort, and occasionally get sidetracked into fixing up the articles or categories I come across during that. I generally do over 1000 edits a month, with 95% of them being minor article edits. I prefer to stay out of Wikidrama, generally leaving alone any area which is being guarded or disputed.
I have done large amounts of gnome work (mainly sorting and minor fixes) in the areas of:
