Meant to post this earlier, but according to Reuters it looks like they might have come to the determination that garden pests don't seem to like "caffeine." Personally, I think the carbonic acid and similiar in soda's a whole lot worse for them (slugs, etc), but... *shrug*

Caffeine Could Be New Environment Safe Pesticide
Reuters
Jun 26 2002 2:06PM

LONDON (Reuters) - Farmers and gardeners determined to protect their plants from slugs and snails may not have to look any further than their morning cup of coffee for an environmentally friendly pesticide.
The menacing molluscs hate caffeine.

Even very small concentrations can be deadly for the garden pests, scientists from the US Pacific Basin Agriculture Research Center in Hilo, Hawaii said on Wednesday.

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