Here's a question: before he gets his wand, Harry (and Neville) can do unconcious magic. And wands work even when they're broken. So why can't wizards and witches do magic without a wand? Potions and charmed items will work without them... hmmm

As for the owl question, it's a tough one, Hal. The owls also travel amazing distances overnight, so I wonder if owls can teleport, too?