This last Saturday, I was at Barcamp PT and started to talk with Nuno Moreno about games, specially online quest-style games.
I remembered an old game, the Heineken Challenge, that was very popular at least here in Portugal. I'm not sure when it was online but it seems 1996 is the correct year.
The problem is that 1996 is like 1BG (1 year Before Google), so I can only find about the new Heineken set of lame flash games.
Anyway, if anybody here can find a reference to this game, please leave a comment, thanks!