>Or does anyone other than Hal work in other bases?

people who work *with Hal use base two, eight, and sixteen.
two and eight are simplistic (base two : 1,10 and eight = 1-7,10)
base sixteen took rather more imagination : 1-9,A,B,C,D,E,F,10

I don't know about 'speaking' base twelve, it doesn't seem very practical.