Bristle Worms?

[fishswim]

I got some live rock today. I am seeing a lot of things "peeping" out of it. The are almost clear. I don't even know what a bristle worm looks like. So what do they look like?

 

[fishswim]

And are bristle worms bad?

 

[twoods71]

Bristle worms can be bad as they can start munching on corals.
However they can be good also as they are scavengers and feed on uneaten food.
I have also read that large bristles have they potential to harm fish.
I have some in my substrate and leave them be. I did find a large one a while back and removed him though.
Bristles are usually a redish color with many small fiberglass looking legs. Do a search for bristle worms on a major search engine to find a photo.