Julian Sanchez wonders about virtual picket lines:

...think ahead a couple years to when mobile devices at least as advanced as the current iPhone are as ubiquitous as cell phones.This makes physical environments potentially dense with information, whether through particular function-specific channels (Zagat reviews), socially salient tags (3 of your friends had a comment about this restaurant), aggregative filtering (a comment about this location was voted above your Digg threshold), or some combination thereof. The purpose of this won't necessarily be to facilitate activismpeople are more likely to want to look at reviews or know if there are better prices down the block. But it also means that political information can be embedded in a place without requiring a bunch of people with placards to spend their day marching around in front of a shop.

...the potential here is to drastically lower the information costs of consumer activism. Relatively few people are going to sit down and do detailed research about all the products they routinely buy. Many more, however, may be willing to whip out their phones and click a couple buttons. When the effort required to import political values into consumption decisions is dramatically reduced, the number of politically-conscious shoppers should increase significantly.

Shopping with an iPhone strikes me as a huge boon to both political and economic market efficiency.

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