Brad is definitely my biggest technical role model by far. A completely open source stack: Linux, Perl (Apache mod_perl), MySQL. Besides creating LiveJournal he created Memcached, Perlbal, MogileFS, and OpenID which power some of the biggest sites (even competitors which he is happy about). He probably holds the record for scaling on the cheap. He's also unbelievably steadfast in doing right by his users. He has lost a lot of control since selling to SixApart, but he's still working hard. His blog is super great reading for wanna-be's like me: http://brad.livejournal.com/
The way he tackles technical issues is inspiring as hell, he says "there should be X" and then hammers away non-stop until it exists.
Does anyone have a link to a video of this presentation?