I didn't try to participate in olympiads, but I started participating in competitions when I was 20. I practiced for ACM ICPC for 3 years, which was arguably my most enjoyable days in my life.

I stopped participating in programming competitions when I was about 24. But now I am 27 and I have started doing them again. I am not as strong as I was (or even close to it), but I am aiming to become strong again. One of my goals is to qualify to the GCJ finals next year (this year I was in Round 3, but couldn't make it to finals).

Joy of solving problems is the greatest joy I've ever experienced.