But for the sanity and comfort of other list users, would it be too much to ask that people with annoying tacked-on .sig's use a personal mail account when posting to the list? I hear Google offers nice email accounts for a reasonable price.

That often results in people sending html instead of a legal sig. People who filter on such sigs are likely to filter on html too. People who don't filter on sigs do filter on html. Choose your evils carefully. brandon