I actually got to work at the Sydney games in 2000! I have four scrapbooks of my adventures. My work involved setting up record keeping devices at the timed venues. Most of the time the venue operators could install the software on their own system... but every once in awhile a coworker and I would have travel to the Olympic Park and check it out ourselves. Tough job, I know!
On our free time my friends and I attended the games. Some tickets were given out by our employer, but the cool stuff (like opening or closing ceremonies) always went to managers. The rest of us got tickets to volleyball or wrestling or table tennis! It was also very easy to get tickets to events. I saw a semi-final of swimming, the finals for women's artistic gymnastics, and the finals for men's handball.