It kind of snuck up on me, but I'm a few days away from my 10 year anniversary at Microsoft. I say "kind of" because I knew I started in June of '95, but I didn't realize I started at the beginning of the month, and June sort of generally snuck up on me. I never imagined I'd be here this long. I was 29 years old when I started, and my longest employment before I started was 4 years of public school teaching (with summers off!). I quit teaching to take a year off to get my masters degree. I was so mentally drained from grad school (oh, the stories I could tell), that for the 6 months following grad school, I worked as a bike messenger. It was sickeningly hard work physically, but gave me a much needed brain-recharge. After deciding the Seattle winter and my messenger career weren't meshing, I worked at a company that made music software for a few years before getting a job at MS.
Despite the unplanned length of my career here, I couldn't be happier about the work I get to do. Every day is challenging and fun, and I get to work with great people. I'm never bored, and I never (or rarely) feel unappreciated. Given the state of the stock over the last 4 or 5 years, those are pretty important qualities.