The guy earns like 200.000$ a day, ...
Since start of selling, minecraft made 7,641,938.3$ total volume of sale, it made 219,666.15$ volume of sale only yesterday, and a total of 768,034 people bought the game. Notch's company, Mojang, just enlarged to six people. Hard to tell the exact profits, but I'd say Mr Persson is a multi-milionaire already.
Source: http://www.minecraft.net/stats.jsp
And here is a personal page where he lists all the games he made in the past. By clicking the links you can directly play the most of them: http://www.mojang.com/notch/