Cool Steel Effect

This can be used in many applications the most popular of which is to use it as a UI slider or knob.
The first step is to create the document, if you want to follow me exactly here's what I began with.

The next step is to get out your Elliptical Marquee tool and draw a circle in the center of the document. I find that the easiest way to do so is by holding Option and Shift and pull from the center toward one corner.  It should have about a 600px diameter.  It is essential that your circle is exactly in the center (see the previous blog post on how to do so).  By now you should have something like this

Now it's time to start building the effect, duble click on the layer to add a Layer Effect and select Gradient.  try to make it look something like this

Yours doesn't have to be exactly the same however the colors on the ends must be the same as each-other and make sure that the gradient style is set to Angle.  After you've finished the gradient you're going to want to rasterize the layer style, If you're in Photoshop CS6 you just right-click the layer and select Rasterize Layer Style but if you're using Photoshop CS5.5 or lower just duplicate the layer and select the two by clicking on one holding shift and clicking on the other and then using Merge Layers after right-clicking one either one of them.  Now go to Filters > Blur > Radial Blur and use the settings below.

After this effect the edges usually blur a little so I recommend trimming them about 10px.
...And ta-da! there's your final effect!

If you have any effects you want me to cover in a tutorial please feel free to leave 'em in the comment section below.

Thank you!