   As long as you don't use DGD commercially, you can treat it as free
software.  Commercial use is defined as making money using DGD, e.g.
a mud that charges players for playing or for certain privileges (even
if those privileges can also be obtained in another way) is commercial,
as well as a mud which advertises for commercial products; using DGD
for a mud on a machine which provides internet access need not be
commercial as long as the mud can also be reached on the same terms by
non-paying players.  Other cases where DGD can be used freely are muds
which ask for voluntary contributions to buy new hardware, or forms of
distribution of the source or binaries which do not charge extra for
DGD specifically (bulletin boards, the FreeBSD CDROM).

   If you do use DGD commercially, you'll need my permission.  For a
commercial mud, permission will be granted for a fee of $100 per month.
Contact me for details (email: dworkin@hippolytos.cd.chalmers.se).
