Should You Apply For Multiple Jobs At One Company?

I wonder if I'm the only one who applies for jobs multiple times at the same company.

It's not that I'm banging my head endlessly against certain corporate walls. These are usually companies with whom I've previously interviewed by phone or in-person. Obviously they haven't offered me jobs -- yet -- but since they've shown some interest in me in the past, I keep going back, turning up at their virtual doorsteps every time I see positions that interest and suit me.