During my teens I was a state hockey rep on 3 occasions. We won the nationals twice after turning around appalling mid-tournament form.
Through these years I played with and against several players who have since managed Kookaburras caps, some of whom are going to London later this year.
Playing first grade when I got a little older I lined up against a few of the gold medalists from Athens. They were no longer heroes to me at that point but I still count it as a major highlight. One thing that hockey (and cricket for that matter) has over footy is that club players get to line up against the stars while those guys are still in good shape and in state/national squads as a matter of course, rather than only if they get dropped.
One of my junior hockey highlights was when I was in a schools team against the Hotspurs (sort of all-stars, ex-Olympians etc), and had to face a penalty stroke from Ric Charlseworth who was then only a few years retired from the international scene. (He scored)
My team a couple of years ago went through the season undefeated, although I only played half the season as I went away mid-year. The year before that we got ourselves into the position where we had to win our last six or seven games to be even a mathematical chance at the finals. In the final round we had to win to steal fourth place and were playing the team that finished top. We were 3-0 down at half time and came back to win 4-3. Two weeks later we knocked that team out (on penalties) in the prelim and went on to win the flag.