Here is an interesting idea that I came across this morning...
I bet a person could easily make a wheeled split wood fire rack dolly out of pallet wood. I don't burn wood for heat, but thought this idea might be interesting to someone who does.
Also, another wood processing aide is the folding bucking horse...
I built one of those a few years ago out of reclaimed lumber, but how easy would it be to just use pallet wood 2X4's and planks? What I really like about this design is that it folds up flat and takes practically no space to store. For bucking up some of those logs, it works great. Works best if you have a helper to teamlift up heavier logs onto the bucking horse.

My dad and I used the folding bucking horse for many years, but when my father passed away, I discovered that I had to cut up too many tree trunks that were just too heavy for me to lift by myself. So, I ended up buying a Timberjack....
For a one man operation, I am able to lift the heaviest trees that fall down and get it up off the ground to cut with my chainsaw. Of course, you don't lift the entire tree trunk, just enough of the end to cut off a few rounds and then you reposition the lumberjack for the next cuts. It is made out of aircraft aluminum, is very lightweight, but impossible to bend. Much better than the jacks with wooden handles.
The wooden handled Timberjacks start at around $50, and I paid about $100 for the aluminum Timberjack. For me, the aluminum Timberjack was worth the extra money. I am sure it will outlive me.
I don't think you could make a Timberjack-type device out of pallet wood, but thought I would mention it here as I was showing pictures of wood cutting aides.
Maybe a bit off topic, but I was thinking about my chainsaw tools because I had big, dead, pine tree that just blew down in a heavy wind last week. I won't get to cut that up until next spring, but saw the pictures of the dolly and the folding bucking horse and thought I'd pass along the pics in case anyone might be interested.