I think it happened to Bourque.
I do think a few names could join that list: Pittsburgh should retire Coffey's #77 and Calgary should retire Al MacInnis's #2
Bobby Hull - Chicago Blackhawks and Winnipeg Jets (not sure if it's still retired in Phoenix)
Gordie Howe - Detroit Red Wings and Hartford Whalers (not sure if it's still retired in Carolina)
Wayne Gretzky - Edmonton Oilers and Los Angeles Kings (later retired league-wide)
Ray Bourque - Boston Bruins and Colorado Avalanche (bit of a joke IMO but if it makes Avs fans happy who cares)
Mark Messier - Edmonton Oilers and New York Rangers
Chelios's number should be retired in Chicago and considering how long he's played in Detroit there's a shot it gets retired there as well, although I'd argue against it.
Interestingly enough, the only franchise to retire a number for something other than a player is the Minnesota Wild, who retired #1 as a tribute to all their fans.
Also, the Leafs no longer retire numbers (since 1933) but instead have an honor ceremony for the player. Once they do that the number goes back in circulation. AFAIK, the only numbers currently retired in Toronto are #5 (Bill Barilko) and #9 (Ace Bailey). Oddly enough, Barilko's number was only worn for 1 of his seasons as a Leaf.