Just read a fun post by a advertising industry writer named Haniya Rae which taught me two things in a short amount of time/space:
1) it quickly chronicled the work of several LA-based artists who take inspiration from the market mystique surrounding certain blue-chip brands, and create new "line extensions" for several well-known and much-beloved products.
2) it definitely demonstrated the need for brands (especially well-known ones) to employ a constant and vigilant monitoring of the social web.
Rae's Digiday article is worth a full read, but here are a few quick examples from the piece:
That Tic Tac-brand sure is "dynamite":
If Fendi made diamond-studded chainsaws I'd be frightened (and not just aesthetically -- can you imagine one of these in the hands of the Wolf of Wall Street?)
And a Pampers air horn (sure to soothe the nerves of both baby and parent):
For the most part, Gronquist and Lewicki's hacks are of the "internet snark" sort and fairly benign in nature; that said, it's easy to see how an artist with the same design skills but more malevolent sensibilities could create similar "off-brand" remixes/mashups that could go viral and damage your product's market perception (or worse, your overall brand equity and ability to sell to today's fickle, impressionable consumers).
On the other hand, the best response in the age of consumer-led "big brand smackdowns" is often to have enough of a sense of humor to go with the flow. Otherwise, if you take too heavy a hand in dealing with trademark infringement, you'll be lined up against explosives and chainsaws of a different nature entirely as the social web community decides that you're the next big bad brand in need of a mean-spirited hackathon.