Google's Fractal Map
Google made a fractal application, based on Google Maps, at juliamap.googlelabs.com.
Though, am rather disappointed. When you zoom in just a few steps, the iteration does not automatically increase enough to get crispy edges.Much better are some dedicated fractal apps. See: Great Fractal Software.
For a basic explanation of the mandelbrot set, see: Mandelbrot Set Basic Tutorial (no complex number needed).