Well I don't agree with the above but it depends what type of photo you are after I guess.
Andrews advice is good for taking photographs at sunset, but if you are taking photographs of sunsets then it's going to be different.
For example, a polariser wouldn't be any good if taking photo's towards the sun as the best results are when this is at 90 degrees. And shutter speeds should be high enough to prevent camera shake.
A good tip is to meter from an area of sky above the sun. I find about 45-60 degrees above is a good point. Also, set your white balance a bit higher to enhance the warmer tones of the scene.
A telephoto lens compresses the scene and can make the sun appear huge on the horizon. Great if you want the sun as the main point of interest.
With regards to protecting your eyes, obviously don't look straight at the sun through the lens, but as the sun is setting and falling behind the smog/atmosphere (which is what makes for the best colours at sunset) most of the light is filtered out anyway.
This example below was hand held, whilst sat on the beach this Christmas ![Smile [:)]](/emoticons/emotion-1.gif)
Metering was from an area just above the top of the frame and white balance was increased to add warmth.
