Greg Mayman wrote in a message to Jay Emrie:

 GM> The abbreviation "d" was used to designate the penny in the old
 GM> British, Australian and New Zealand currencies.

It still is when you're buying nails.

 GM> L.s.d, using a curly "L" with a cross stroke, represented libra
 GM> (pound), shilling = 1/20th of a pound, and denarius (penny) = 1/12
 GM> of a shilling.

I never could figure out why the C64 had that key on it.  :-)

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