Member Rara Avis
I agree with Craig; frames do have a place in this world. In fact, I access these forums through a frameset, with the links I need to the left and the forum pages on the right. But the place for frames is almost always one where you know you'll have limited visitors, usually just yourself or a few members of your company/family.
Why? Well, for one, there are very few search engines able to index a framed web site (there are important exceptions to this, better discussed in the Promotion forum). So a lot of visitors probably won't even find you. And if they do, they are going to have trouble bookmarking anything except the frameset. So, if they find a really good reference three levels deep into your site, they have to just remember how to get to it the next time they need it. Frames are very hostile towards repeat visitors.