They are pretty expensive to not know if employers respect there cert. ... I think certifications are a good thing if they are from widely known and respected authorities on the subject.
Exactly. Because if you say in an interview, "CIW certifies that I'm skilled in XYZ," and the interviewer says, "Who's CIW?" then immediately you know that the certification has no value at all.
If the W3C itself truly certified developers, that could be valuable. Or if prominent and respected people in the Web world, such as Doug Crockford or Steve Souders, vouched for a select few people, that could be valuable.
But, unfortunately, I don't know of any widely respected authority that offers certifications. As far as I know, one doesn't exist. And any money you spend for a certification from some random organization is almost certainly going to be money wasted.