I recently picked up a copy of Future Music magazine that came with a CD containing "Tack Piano" samples recorded from an Abbey Road Studios piano apparently used on some Beatles recordings.
What's Tack Piano? I'm a guitarist primarily and I'm not familiar with this term
It is when you place thumb-tacks on the piano hammers, so instead of hard felt hitting the strings you have metal tacks. Gives a brighter, harsher kinda (dare I say?) metallic sound.