For me its accomplishing something by the end of the day.
I've been in IT for a few years now and I've noticed that the thing that keeps my morale up is being able to say "I accomplished something" at the end of each day.
I've found that accomplishing something is more important that my rate of pay or the tools and technology I use. If I run into a patch where I go for days or weeks...or worse months...without feeling like I've accomplished anything worthwhile...I find that my morale begins to drop to the point where I feel I need to move onto something else.
So what keeps you coming back to your job each morning? The pay? Technology? good co-workers? threats from your boss?