Some mini bases (2 & 3mm thickness), more often when the mini has an integrated base already and I just want to "round it out" so to speak. I was going to use some 30x60 pill bases for my Beasts of Nurgle, but when I got them they looked wrong and I opted for 40x60 conventional (although PLA printed) bases. I used MDF pill bases for my Squat bikes and they looked right, whilst I think a thicker conventional base would have looked wrong.
Some pieces of terrain, I've a handful of random blob MDF shapes that I'm slowly using up on scatter terrain, most of my graveyard scatter terrain is on MDF. For larger pieces I tend to use foamed PVC sheet now and with resin where I just need to tidy up the edge I'll use plasticard to avoid adding any real thickness.
So not much overall (I would still love a laser cutter however, to cut, err stuff)