F-Bomb

That's F for Flower. A PVA water soluble weapon of mass foliation. Otherwise known as a Seed Bomb deployed by ninja gardeners to sew seeds in hard to reach places. See Also: http://www.guerrillagardening.org/ggseedbombs.html

Sure, there are cheaper and more efficient ways to do this... but... pfft... The idea is to stuff it with some compost and seeds and then throw it somewhere that you think could use some color, but you either can't get to it or it's where people wouldn't appreciate seeing you digging around. Then wait for mother nature to dissolve the shell and make some magic.

This of course requires water soluble PVA http://www.makerbot.com/blog/2011/02/21/makerbot-introduces-water-soluble-3d-printer-filament/ since you don't want to wait a thousand years for ABS to go away. I'm not even sure this will work, however PVA is supposedly bio-degradable http://www.eliteanglingproducts.com/PVAEnvironment.asp and is used as a seed coating http://www.celvol.com/sekisui/sek_seed