I know, it sounds pretty silly, talking about soap bubbles on a bike blog. But did you know that simple dish liquid does wonders on grease filled hands? I've never bought fancy products for this dirty job. The trick is to work the soap directly into your hands. Don't bother with water as this dilutes the effectiveness. Rub for a while, then simply wipe it off on a paper towel (or rag that you will dispose). It's amazing. Nearly all the grease is gone.
I forgot to wipe my pinky on the towel or that would be visibly cleaner.
My husband and I substituted shampoo while touring. Hair soap does double duty as body cleaner and bike maintenance cleanser! Soap up, rub hands in the grass, and then rinse with water from our bottles. All clean. Smelling like roses or Dove or Suave—whatever your preference.