In 2008, Japanese beverage company, Suntory ran a Transformers promotion on their line of Boss coffees. The oversized plastic caps contained a random Autobot or Decepticon PVC figure based on the color of the cap, red or purple.
The figures are small and rather simple, but there is more than meets the eye here! Underneath the cap is a small hexagon shaped paper insert that shows off the other figures in the series. On the flip side are different little diorama images. Simply fold the insert to display the image you want and then insert it into a small ridge in the top of the cap and you've got yourself a rather nifty diorama display!

I should have put a SFC figure in the picture for scale purposes as these little guys are fairly small. There is a small bit of assembly required when you first remove the figure from the cap. Usually it's just attaching the legs to the upper half of the body. To be so simple of a figure, I was surprised to see a few paint apps. I also didn't expect the PVC figure to contain much detail, but if you look carefully on Astrotrain's wings you'll see a small Decepticon symbol!
I know these type of things don't appeal to every Transformers fan, but I find them fascinating and best of all, they don't take up much space on my display shelves!