I rode a 1983 Nishiki Olympic 12 to work for about 6 months this year (I was cycle commuting about 1/3 of the time at the point). I bought it new in '84, and it was just hanging around in the garage when my work site changed I was suddenly less than 10 miles from work.
The second time out, I hit the end of a sidewalk and went over the handlebars. I bent the fork back far enough that the tire was behind the down tube. The down tube itself was buckled a bit just behind the head tube. I bent the fork back and continued to ride it until I finally got a replacement for it at the end of August (which happened to be another Nishiki):
I also happened to pick up a 1960s Raleigh 3-speed, and I've ridden that to work too:
So, yeah, I know about riding old bikes.