(2007/12/22) UPDATE: We've found our paranoid. :)
For the past 2 years at Yahoo!7 we've been continuously hiring software engineers. Last week we began advertising a more niche position for a paranoid yahoo. CNET wrote a nice article on the paranoid yahoos.
Essentially the role is about being part of the global paranoid team, based in our Sydney office. The paranoids look after all aspects of security but the core of the job revolves around protecting our users and ensuring the security of our sites. You'll be expected to provide training, guidance & advice on security matters to yahoos across the business. If you appreciate the technical beauty of great hacks, and understand the tradeoffs between absolute security and functional/business objectives then this job is probably for you. There's loads more details in the job ad.
If you're interested and have any questions feel free to drop me an email. I currently perform this role part-time (one of many hats) but I'm not the hiring manager so if you impress me I could put in a referral. :)