I just filled a trash bag with packing peanuts. I hate getting keyboards in packing peanuts. They are unwieldy, leave little pieces of styrofoam everywhere, and are very environmentally unfriendly.
Please use some combination of crumpled up butcher's paper (my favorite), bubble wrap, or those plastic air pillows (nice, but the equipment is expensive).
Also, I have had some keyboards shipped to me in shredded computer paper, which also annoys me. I have no rationalization for that complaint, though.