I look at the rep number to see if it has changed. For Jon Skeet he must get tired watching that number change every second.
Oh and Hi. It's Friday here.
I look at the first question, and check it that I already seen or not.
I look at the little envelope to see if I have any replies.
10k tools > Most Delete votes. I just love deleting.
(That's a joke, people. It's Friday.)
Perhaps very stupid, but I tend to check the count of the tags I look at. I don't look at every question in those tags, so knowing that a new question popped up is easier to me by just seeing if the number changed.
I use a chrome extension for rep monitoring (StackOverflow Reputation Extension By Guy Vider http://www.TravelingTechGuy.com) so the first thing I do is click on questions and check the first page to see if the questions seem answerable (excluding accepted answers).
Just recently I've been obsessed with which user page I'm on on SO, and I've drifted into the top 200 (https://stackoverflow.com/users?page=200) which, BTW, is in the top 5% (in terms of rep) of registered users on the site. With about 181,000 registered users I'd like to move into the top 1%, but that will require a move from 1,200 to 4,200 rep - which will take a while and will probably be closer to 5,000 by the time I get there.