I don't compete with other cyclists going into work. But I do take some pleasure in attempting to catch (I never pass unless my cruising speed is significantly faster than theirs) people on the way home. Just yesterday morning I caught a 'Bent rider right before the turnoff to my apartment. Never been able to catch one of them before.
I do confess: I totally check out other peoples' setups and whether they have better light systems than me, more expensive panniers and the like, how well maintained their ride is, etc. I judge silently.