"I remember working with nothing but ones and zeros; we couldn't even afford ones for the early stuff. Had to do it with nothing but zeroes..."
OK, you win. 
I did do defines when I would use an oddball instruction or two, like SIM and RIM to set/read the interrupt mask on the 8085 (8080 did not have those instructions and I was using an 8080 assembler) and I have punched in boot sequences from a cheat sheet by jand. But hand assembling more than a few instructions? No...