I have certainly played Scrabble games with people that though you could re-use bonus squares, though I haven't heard of the distinction you make between word and letter bonus squares. I think this is not so much a common variation as it is a common misconception (like Free Parking in Monopoly).

I have had reasonably-good success weaning people of their attachment to this non-rule by purposely making solid blocks of tiles that have to be carefully lifted and replaced for every word I play :-)

Scrabble variation: use double and triple word scores (but not double/triple letter scores) twice?
Because I am trying to process an immigration work permit for Canada, (I am an American citizen), I need to fly directly into Halifax from the States.  I am trying to make sure that I don't clear Canadian immigration and customs in the Philadelphia airport.  (For instance, when I fly from Toronto to the USA, I clear American immigration and customs there.)  Any ideas?
