Link: http://www.sitmo.com/latex/
you can type you LaTex's markup scripts and then download the equation photo from the plugin.That's very interesting. For example, i typed:
P(W)=&P(w_1)*P(w_2|w_1)\\&P(w_3|w_1,w_2)*P(w_4|w_1,w_2,w_3)\\&P(w_5|w_1,w_2,w_3,w_4)*......
Then i can get:

Besides, you can add it to your iGoogle. It would be cool and helpful.:)