[ExI] stretching the pandora concept

[spike]

An interesting aspect of Pandora is that the music selections it chooses
converges, regardless of which music group one starts with.  I started one
with James Taylor and another one with Abba, and eventually, after I thumbs
upped and thumbs downed a few dozen selections, it converged on remarkably
similar collections of music, even with wildly dissimilar starting points.
So if one knew nothing about any music, and only voted up or down, Pandora
could perhaps eventually find good material suited to ones taste.

So, could not this concept be expanded?  Is there something analogous to
Pandora in the literature world?  How about in art?  In pornography?

spike