Re: Low cost weight sensor ?

Anton Erasmus wrote:
... Have anyone used piezo electric material to
measure weight ?

Yes, there are piezoelectric load cells. They may be difficult to use
because they require very high impedance analog circuitry to read the
output. ("Charge Amplifiers") See:

http://www.kistler.com/do.productfinder.us.en-us?content=833_ProductFinder_Force&param=3XXX.9021A

Would a piezo speaker be suitable ?

May be... How stable will that be?

.