Google has never made sense to me. It seems like such a paradoxical organization. Clearly they are generating vast amounts of revenue, but it seems like all of their best products are completely free. Adding to that list is the ability graph functions through a simple Google search. Follow the link for a demonstration (sorry for the sarcasm):
Graph of the Sine Function
You can change the scale easily and it has an extremely fine trace function. Now, they just need to design a way to find roots and points of intersection and it would be really amazing! You can also graph multiple functions at once:
It is against my nature to think a company the size of Google could possibly be "good", but man they are generous with their technology.