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the students worked in small groups to design and launch
software to support some form of group interaction. To anchor
the class, I required that whatever project they came up with
be used by other ITP students.
…

What I hadn’t anticipated was the second-order benefits. Time
and again the groups came up against problems that they
solved in part by taking advantage of social infrastructure
or context-sensitive information that wouldn’t be available
to adherents of the Web School. Two strategies in particular
stand out.

The first had to do with reputation systems. … Because money was involved, a Web School approach would require some way of dealing with the threat of non-payment, using things like pre-pay or escrow accounts, or formal reputation systems.

Instead, in both projects the students decided that since all
the users were part of the ITP community, they would simply
make it easy to track the deadbeats, with the threat of
public broadcast of their names. The possibility of being
shamed in front of the community became part of the
application design, even though the community and the
putative shame were outside the framework of the application
itself.