All you need to do is type basic and complex math functions into the Google search box and Google will return neat graphics. From basic charts for sin(x) to more complex graphs for x/2, (x/2)^2, ln(x), cos(pi*x/5).
Of course, Google gets their ‘geek on’ by showing off their math skills:
Did I mention you can zoom into these charts?
This is Google’s graphical calculator, right on the search page.