SKI calculus is pretty neat, too. You get no tape, no counters. (But it's not quite as bad to program in as brainfuck, because you can built more ergonomic contraptions to help you along.)
SKI can, of course, be de-optimised a bit further by replacing I with SKK. You are right though that it is relatively simply to go from something that looks like a normal program languages to a pile of S and K combinators. Not the most efficient way to compute though!
