Is there a calculator...

[sa-penguin]

A calculator [or equivalent] that does DSP?

I'd like to explore filters (FIR, IIR etc.) and it seems the most logical self-contained unit would be in the form of a calculator.

Yes, it would need an ADC [and preferably a DAC as well] but the main thing is the ability to access a series of registers, containing the variables that define a filter.

Does anyone know of such a beast? Or should I be looking at small netbooks?