well, I don't like the Olympic Games! There are so many sports, that's fantastic, but in Germany you can not trade them seriously. TV coverage is awful. They are jumping from sport to sport, so you do not know which sport is really live covered and which sport is a replay.
They also show boring sports like shooting or sailing. You can not trade them!
The tennis event at the Olympics is in progress, but there is not very much liquidity in Betfair markets and there isn't a working scoreboard for trading.
I took the time to do some paper trading of soccer. Last weekend German's football season has started with the first round of German Cup. At the moment I am in profit 'on paper' and I will have a look at the first matches of the German Bundesliga Season 2008/2009. I will try some strategies on Match Odds market and Correct Score market.
Actually I can say, the most powerful tool for trading these markets is using a stop loss. I will update my progress on paper next weekend.
Wish you all the best with trading!