STOHara said:
There are also people who read forums from work and don't want their cow-orkers to think they're looking at naughty sites on their lunchbreak.
As I do surf at work (and don't worry, the boss knows and doesn't care!) I can tell you that the issue is more the risk of the site getting blocked than co-workers. A LOT of companies use anti-smut, anti-spam (anti-everything) software to block certain sites. If the algorithms decide a site hits certain criteria, it will be blocked...from ALL computers across the network.
For example, if you use some file-sharing services to host images in your posts, all I see is a big empty space. The company software blocks anything from certain file-sharing sites. Some images, even in the signature lines, do not appear to me on my work computer depending on what you named the file, because certain "buzz words" trigger the anti-porn filter.
I actually have been somewhat concerned recently by some of the erotica signatures. Not because I am offended, but because between the images and the text, I'm afraid they will eventually trigger the anti-porn trigger.
I don't want to turn off signatures, though, because I LIKE some of the signatures and I use signatures sometimes to check out people's books.