spugnews is a GPL'd usenet binary grabber. It has a simple command-line interface and the ability to perform rudimentary subject line analysis to group together articles that are part of the same file set.
Documentation
internal yenc decoder (not as fast as the yenc module, but good for the
impatient)
work around for problem with hex encoding in newer (2.3+) versions of Python
that affects yenc CRC check.
status indicator for header refresh.
incremental header writing (so if there's a problem when in the middle of
downloading thousands of headers you don't loose what you've got so far)
Initial release.
Change History