Today I received a Casio fx-85GT calculator as a present from a couple of my friends. It gives expressions in exact forms as an alternative to the ordinary decimal output. For example, enter: sqrt(8) and it will output: 2*sqrt(2) Of course, I believed that the calculator was performing symbolic manipulation -- very impressive for a handheld scientific calculator! However, I then decided to test it: ln(640320^3+744)/sqrt(163) Instead of displaying the correct answer, 3.14159265..., a prominent image of the Greek letter pi was rendered! Hmm... I'm waiting for a version that prints "stop trying to test my symbolic calculation facilities with well-known near-miss identities!" On this topic, there is this comic: http://xkcd.com/217/ Sincerely, Adam P. Goucher