As mentioned in another thread, I'd like to get more use out of the 1-2-3 blocks that I have. Thus, I encourage people to add pictures and descriptions of the creative ways they've used their 1-2-3 (or whatever it is in metric) blocks.
I'll start things off here by posting a picture of how I usually use them... as spacers. Sometimes they work, sometimes I have to go digging into my steel box to find something a slightly different size.
Here's one of the ways I mount my 6" rotary table to my Craftex B2229 mill/drill/lathe:
