As mentioned on the Reducing Noise in Cycles [Wiki Page](http://www.blender.org/manual/render/cycles/reducing_noise.html?highlight=reducing%20noise) you could try Filter Glossy or other techniques listed there.

If you're rendering a static image you can use the Seed value for Cycles to save a couple versions of an image and use the data from the second to remove fireflies from the first. See discussion and an example image of that [here](http://blenderartists.org/forum/showthread.php?216113-Brecht-s-easter-egg-surprise-Modernizing-shading-and-rendering/page193)