[MP-Ryan]

http://www.eurekalert.org/pub_releases/2011-05/asfm-tro_1051811.php

Michaud's research is part of a growing field of study focusing on bioprecipitation, a concept where bacteria may initiate rainfall and other forms of precipitation including snow and hail. The formation of ice in clouds, which is necessary for snow and most rainfall events, requires ice nuclei (IN), particles that the ice crystals can grow around.

"Evidence for the distribution of biological IN in the atmosphere coupled with the warm temperatures at which they function as IN has implied that biological IN may play a role in the Earth's hydrological cycle and radiative balance," says Christner.

Not just hail, either.  I wonder... genetically-modified weather? *searches frantically for a tongue-in-cheek emoticon*

[Snail]

Oh God that is so cool. Imagine if you could manufacture like specific strains of weather microbes and weaponize them.

[BloodEagle]

I suppose that it's better than when the Russians tried seeding clouds with concrete dust.  You know, since it didn't work... and killed some people.

And if you can make it rain blood, I'm all for it.

[Flipside]

If you screw with the weather, the chances are it'll screw you right back

[watsisname]

1:  Grow a field of grain and hops in tornado alley
2:  Wait for a tornado to raid your field
3:  Shoot yeast into it
4:  ????
5:  PROFIT