Here on HighscoreGokkasten.nl you'll see a variety of online slotmachines which you need to play for a highscore.
You deposit 1,30 and you'll get 100 points. Play with these credits for a highscore and enter your score in the Top Score list.
The top 3 are winning prizes. The Battle4Cash machines are random, the other slotmachines you play for the 2nd, 4th en 6th place. Which place you have to get is decided by the computer with a random option.
Look at the machine menu for the prices and the place you have to reach to win. Click on a link/banner, dial for a code, subscribe a username which you will see back on the toplist and get ready to play.