Which is the most profitable online casino game?

Online casino sites also have a fun mode where players can play and learn to play and before they decide to play for real money online. Playing for cash can produce great feelings as well as huge adrenaline rush and is very exciting. Many online casinos offers their online games in fun mode for nothing and most of the time you will not even have to download their online casino software.
Between all of these games available, online roulette tables have for most of the time one of the biggest jackpots available online, followed by the game of blackjack. In the UK it is possible to find both American and European roulette games, but the roulette progressive just is another version separate from American and European roulette.
There are also other games available in online casino sites that have smaller jackpots, such as video poker games and of course the slot machine. This said some of these games have some very large jackpots; 100x video poker games, 20 and 50 line slot machine games. Indeed these have very large jackpots, but who can tell me which the most profitable online casino game is?
In fact this a very difficult question and the reason is that, it often depends on how long you are playing and the amount of money you have gambled.
These games above such as the roulette games, often dependant on how much you gambled can have very large jackpots as for the 100x Play video poker games, any progressive game could have an infinite jackpot.