A way of thinking about programming introduced by James Noble and Robert Biddle. The essence of it (at least for me) is that software development has long had a modernist viewpoint that admirable software systems are composed of uniform components, composed in a uniform and simple way. (Smalltalk and Lisp are good examples of this kind of thinking.) A post-modern view is that software is all sorts of different very different stuff glued together in all sorts of different ways (think Perl and Unix), and this style of software (big bucket of glue) isn't a bad thing.
To read more try the original Notes on Post Modern Programming, just beware that it's written in a post-modern style which means it lacks a grand narrative. If you have access to the ACM digital library you can also reach the follow up Notes on Notes on Post Modern Programming. You may also be interested in the scrapheap challenge workshop. They've also set up a (at the moment rather empty) web site.