I'm all for recycling and reusing, but an incident in New Zealand shows that prudence may need to be raised with our environmental consciousness.
Two women in a restaurant had to be hospitalized after tasting what they thought was mulled wine. Instead, it was a dishwashing liquid with sodium hydrozide. The mixup apparently occurred because an emptied bottle of "Mountain Thunder" mulled wine had been filled with dishwashing liquid. Though a detergent sticker had been slapped onto the wine bottle, enough of the original label still showed to convince a server that the vessel still contained the requested mulled wine.
For more details, check out this article from The New Zealand Herald.