http://www.flypentop.com/

Here's a description from Playthings.com:
"The new FLY Pentop Computer platform, LeapFrog, Emeryville, Calif., brings pen and paper to computer. The electronic device gives users real-time audio feedback as they write and draw on special FLY paper. Users can draw a calculator, touch the handwritten digits and functions to perform an operation – then hear the answer announced from the FLY Pentop Computer. With the FLY Through Spanish software, a user can write a word in English, touch the handwritten word, and then hear the word translated into Spanish as it is spelled out and then pronounced. The suggested retail price for the FLY is $99. Accessories range in price from $24.99 to $34.99."