Sure, I'll buy this - but the shared pain would of course be lessened
    even more if the sellers would credit the authors fairly, and share the
    profits - don't you think? :).

You're assuming that the published code is resold in source form, in which
case of course proper credits are to be preferred.  Plagerism is still
plagerism even if the works copied aren't copyrighted/etc (try turning in an
english assignment copied from a famous long-out-of-copyright author :-) I'm
concerned that restrictions aimed at preventing someone from republishing
your source can also prevent anyone from including the code in object form
(ie in a physical product.)  PIC-based gadgets aren't well suited to listing
out a long series of credits, and (end-user) documentation tends to look
weird if it starts talking about random people who contributed bits and
pieces of the final product.

(Try actually shipping binaries based on modified gnu copyleft'ed source,
for instance.  What a can of worms (assuming your product itself isn't open
source.)

BillW

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