Hockey Numbers

I hope some of you can answer. This has always interested me.

Has anyone wore #4 since Bobby Orr retired ?

Has anyone wore #66 ? I know #99 is off limits.


Why do so many goalies wear #30 ?
Tim Thomas, Lundquist, Brodeur, and a few others.

I know Cheevers had #30, but why is #30 such a common number for goalies ?


Who started the #19 trend for center icemen ?
Joe Sakic, Jonathan Toews and many other quality centers have worn 19.

Did Bryan Trottier start the trend ?