Extended Piano Technique

I am writing a piece for myself to perform, using only extended piano technique. I will not be playing any unaltered, natural tones. I am already using pluckings, strikings and other abuses. I also made mutes with tongue depressors. I wonder if you people know of any extended techniques I don't, or if you've made up any. I desire them.

I'm a fan of harmonics, especially on lower strings. Sorry for the lack of information - I don't know how/why they work, or which ones are possible...but they're cool.

Also, preparations such as ball-bearings are fun.

just above the damper there is a third. it's pretty easy to hit. the rest is relative to length. it's good to find the harmonics you want and mark them with a small sticker around the string.

if you use the sustain pedal and gently play the lower strings like a drummer plays the snare with whiskers you can get a nice thunder effect.

a number of table tennis balls inside the piano with a closed lid is also funny.

If you use a glass like a cognac glass and moisture the top edge and circle it around in a small circle whilst playing a minor second as a trill you get a siren like sound.

Tie a fishing line to a string and rub it with a piece of amber.

It is not called ext piano but prepared piano