This is probably a post for the UK members more than anything, but I guess it could still be played by our overseas friends. On the BBC website there is a game called celebDaq. Its like aa virtual stock market, but instead of shares in companies, you buy shares in celebrities. Prices change according to the newspaper coverage of each celeb.
I thought it might be a nice idea to have an iex competition. If you sign up, you can join the mini league named "iex".
Take a look and see what you think.
http://www.bbc.co.uk/celebdaq