The easiest job is one that is challenging enough and satisfying enough to be rewarding, but also has some routine aspects that keep you so busy that the day flies by. The best job I ever had (not considering pay and benefits) was running a large flat-bed gang-saw in a mill that made cabinet panels for Scoville/Nutone, etc. Setting up the saws, getting precise trims, minimizing waste, etc, etc, was demanding, like doing machine-shop work, but with materials that were not as predictable as metal billets. The great part was making long runs of cuts, feeding big laminated veneered panels to the saw for hours at a time. I could stand there working while composing lyrics or thinking about stuff while the day just flew by.
Edit: Probably second-best was mucking out the stalls in my uncle's Hereford tie-ups. You always accomplish something, the job is never really done, and the cattle really like it when you give them a little grain, and scratch their heads roughly, and slap them on the flanks calling their names. I never got kicked (something you can't always count on in a dairy environment) and as long as you respect the hierarchy of the herd, the matriarch will be your friend.
