My longtime goal had always been to expand my Polish Early War army with the motorized cavalry and the cavalry arms of the Polish 1939 army.
A small step on the way to a motorized army is the Motorcycle platoon. Game wise they are a tad expensive, but contribute with some valuable "reconnaissance" rules while mounted up. Battlefront had a box of these earlier (not sure about now) and I bought the last 2 boxes from a store here in Sweden before the range disappeared into the re-packaging void that hit the Polish EW range earlier this spring/summer.
Full review on my blog:
http://anatolisgameroom.blogspot.se/2012/07/battlefront-ew-polish-motorcycle.html