I do think it is the most beautiful equation I've ever seen. To me, if there is any evidence for a God in this universe, that is it.
Good choice. Feynman thought it to be "the most remarkable formula in mathematics".
Euler's solution to the Basel problem (which inspired Riemann when he defined his zeta function) has an elegant result:
The Gaussian integral expresses a beautiful result, too (which can be evaluated using polar coordinates):
Then there's the Mandelbrot set, given by the quadratic recurrence equation
Interestingly, it's possible to use a very similar, cubic equation to produce a three-dimensional mandelbulb
. (Although as far as I know, it hasn't yet been shown so far that this is a "true" 3d analogy of the mandelbrot set.)
More later. Also, as the public speaker of ancient Greece noted, LaTeX isn't working properly on this site. Solve.