Introducing SJ to a World

Morning Fellow Jammers!
   Well I'm writing this as I have my breakfast so sorry if there are too
many spelling mistakes...
   I woke up today thinking a lot about SJ, so I came across a little
question...  In my campaign I introduced SJ to the "main world" by creating
some proto-spelljammers on the world, not that I want to bring up this
groundling and spelljammers thing again though, also I placed the sphere in
a convenient place, I think it was off the 'back' of Realmspace on a one-way
current, the thing was that there is ease in reaching the sphere so there
were also other spelljammers who came in to introduce the stuff, build
dry-docks, etc.
   But I was wondering how did the rest of you introduce it to _your_
worlds?

        +~~+
       ^_  _^
        %  %
        /  \                         "We don't have to breed,
 _-#*__|    |__________________*#-_    We can plant a house,
@   jpembert@??????.??.???.??.cr   @    We can build a tree,
 ~-#+~~|    |~~~~~~~~~~~~~~~~~~+#-~    I don't even care,
        \  /                          We can have all three"
        %  %
       _~  ~_
        =__+

PS Special Thanks to Sean Reynolds for that wonderful WGW Catalog!