Founder of Fog Creek Software, which makes an HTML editor/content manager called CityDesk, and, in many people's opinion, exceptionally nice bug tracking software called FogBugz?.
His weblog, JoelOnSoftware, http://www.joelonsoftware.com/, has lots of great articles on software.
Reviews:
JS has a clean and vivid writing style - a major acheivement considering the subjects. The drawback is when he's completely wrong he is very hard to counter. --PhlIp
His essay on "Five Worlds" -- http://www.joelonsoftware.com/articles/FiveWorlds.html -- sheds a lot of light on his skepticism about XP. XP methodologies are very effective in corporate-internal development like the storied C3 project, where requirements can change at any time over the course of the project, but they don't exactly add a whole lot when writing shrink-wrap software (his preferred world), and they'd probably be actively obstructive in embedded-software and game development. (There's a reason embedded and games are almost exclusively CeeLanguage and CeePlusPlus.)