Here's my fixie. I splurged a few years ago on a Wabi steel bike.
When I got my first road bike in 1961, I doubt I thought I'd still be interested in, much less capable of cycling when I'd be 67. I am, though. My mileage has dropped off the past couple of years, but I still love riding my bikes (road, mountain, carbon, alu, and steel), none more so than my fixie. I don't often see older fixed gear/ss riders in Los Angeles, at least in the areas I ride (from downtown to Santa Monica and Malibu) but I know they're here.