Leaf-cutting ants.

Acromyrmex and Atta.
Atta species demonstrate one of the most elaborate social organizations known for any kind of ant.

If you are interested in Leaf-cutting ants find out some useful links below:
  http://www.sasionline.org/antsfiles/pages/atta/Atta.html - good for starters, serveral pictures.
  http://www.thewildones.org/Animals/atta.html - short, but with unique pictures.
  http://www.insecta-inspecta.com/ants/leafcutter/ - drop in before going on a vacation to Guatemala :D
  http://www.sci.mus.mn.us/sln/tf/f/fungus/fungus.html - take a look at the atta movie.
  http://troyb.com/photo/gallery/section32.htm - nice gallery.
  http://ag.arizona.edu/urbanipm/insects/ants/leafcuttingants.html - another info about leafcutting ants.
  http://www.blueboard.com/leafcutters/images.htm - great gallery.
  http://animaldiversity.ummz.umich.edu/site/... - excellent science pages.


Atta Ants game.

Yes, this is a board game too.

If you are interested in Atta Ants game follow the links below:
  http://www.abstractstrategy.com/atta-ants.html - strategy resource.
  http://www.boardgamegeek.com/game/8128 - let's play!