The gear scanner and gear scanner interference aren't that impressive to me as its mainly PvP related i guess....
Mailbox i've heard from but i suspect its not implemented or something =(
I've seen more things mentioned in or around this game thats not implemented yet so.
Like on one link about crafting they're talking about recipes sold for higher level - they're nowhere to be seen, then theres these chips and the engineer class ofc.
The 'first' wish as you call it is a quest, its not a real wish.
You can not wish for anything else but the package containing 10k zeni, dragon chip and lv20 shenron rares.