A few years ago I interviewed for a job at a well-known software company. On my resumé, I had listed the URL of my blog, as well as several other websites I'd developed. I did this both to provide work samples and in the hopes that they might actually read my blog before my interview and learn something about me. As it turned out, none of the ten or so people who interviewed me had even glanced at my website. I didn't feel like they understood me at all. Many of the questions they asked were stupid to the point of being insulting. I went away from the interview half-hoping I wouldn't get the job, and luckily I didn't.
When I interviewed at Kryptiq, one of the first things out of the first interviewer's mouth was, "So I checked out your blog...". He proceeded to ask me intelligent questions about my open source projects. In fact, much of the interview consisted of talking about Poseidon and ReferrerCop. Several of the other interviewers also mentioned that they had looked at my website. It was a refreshing feeling, because it's impossible to convey the entirety of my skills and experience on a two-page resumé, but these people obviously cared enough that they had dug around and done some research. As a result, they knew a lot more about me than was on those two pieces of paper. I walked away from that interview with a good feeling about the company and, as fate would have it, I got the job.
This website, in its various forms, has been a tremendous asset to me over the years. It earned me several elective credits and made me into a mini-celebrity in high school (seriously, it did), it's been instrumental in getting me at least two jobs, and it's served as an invaluable creative outlet.
Blogging may have become passé years ago, but it still has its benefits.