This library provides a bare-bones implementation of some complex math, particularly an implementation of the Riemann Zeta function.
It also implements a colorwheel chart generator, which can create some very pretty wallpapers (see examples/).
JavaScript isn't exactly great for math, but the accuracy of this library is sufficient to provide faithful renderings of the zeta function, provided the real input is greater than about -18.
More docs and examples. Other special functions. Handle multi-valued complex functions properly. Add a quaternion implementation. Browser testing.
Jason Lawrence