Crating with Basswood adds a nice effect to 1:50 diecast parts which can be used as loads on flats.
Here is a video that shows a Crated Caterpillar D10 being lifted from a O Scale TTX flatcar to a lowboy.
The Crated dozer blade and separate arms are lifted to a flatbed trailer.
Not sure how to upload the video, so here is a link to it.
You can take apart any model of you're choice, build a crate as a base and you have a unique looking piece.
So many different possibilities.