Okay, I'm no CSS wizard, hey, this site hardly uses CSS (at the moment), but CSS boxes are rubbish.
Okay, CSS wizards - I challenge you to create a page that has three vertical columns, with the side columns of specific size, with the centre column consuming the rest of the width. I'd like a little margin on left and right ("space to breathe", so to speak). I'd also like the centre column to have a banner at the top - that's got to be fixed size too. Oh, and I'd like a top and bottom margin too.
Now, I can do the above really easily with a table. I just make the width 95%, put a spacer image above th table, and then create three columns, with two rows - the outer two columns spanning both rows, but the centre column having the two rows. The top row has an image in it that sizes the row, so creates the fixed size.
Can this even be done with CSS? Easy in tables, provided you want to mix style and content. Very hard in CSS - even called "the holy grail" at glish.com! I don't think it's practical in CSS...?
(that said, CSS is very handy for all the other things, like font types and appearance of text - all stuff that will get incorporated in this site sometime soon).