Forms of Transportation

[K G]

No: HPFGUIDX 99899

Susan's post about her son's question got me to thinking about an observation my own son had a while back.  In each book, a new form of transportation is introduced.  
 
SS - hogwarts express, magical boats
CoS - Floo Powder, flying cars
PoA - Knight Bus, Hippogriff
GoF - Apparating, Port Keys
OoP - Thestrals, Portraits
 
My question is, if we keep on this same vein, what will be the next forms of transportation that we will see?
 
Moonmyyst (who really wants a flying carpet)