Theo de Raadt, OpenBSD's benevolent dictator for life.
Theo's unique vision for what and how BSD should be developed and implemented inspired his offshoot from NetBSD. Those same ideas permeate the architecture and documentation of OpenBSD, that spades should be called spades, and emotional attachments to poor implementations have no technical merit, and ultimately technical merit (which encompasses a lot of other ideas) should win out in architectural decisions. Theo's background in software security, security problems in NetBSD, and early partnership with various entities in the then fledgling network security industry show their influence in Theo's passion for a secure, by default, Operating System.
Addition: If there were more people in the world like Theo that spoke their mind there would be a lot fewer problems. His leadership and the OS rival no other.
A link to his standing up to corporate a**holes or their behavior. Is OpenBSD better than NetBSD? Hmm... I think I understand now why he didn't have access to the cvsup tree...