I have just done a major update on my "Getting Rid of Ground Moles" niche site.
It is not "pretty" yet - I am not a graphics designer, and I am still very rusty on the HTML.
It does use a nice neat trick that I haven't seen anyone really talk about before. (though I haven't searched)
You may or not be aware that spiders/bots start spidering your site at the top left hand corner and work their way to the bottom right.
Now I have read SEO experts state that you should have your menu bar on the right hand site so that a spider doesn't go chasing links to other areas of your site before it has had a look at your content on a page.
What I have done is used a floating DHTML menu on the left, but the code for it is after the H1 and H3 content.
I do have a second menu at the bottom of the pages to ease navigation, as I am not sure how well the DHTML degrades with browsers. Also, to help with the degrading, my DHTML code is currently before the main body of my text, so the menu doesn't appear in an odd position if something doesn't quite work out. I don't know whether this will work the way I planned. Sometime in the future I will have to test it. In hindsight the code should really be in a cell on the right hand side of the page (even if the menu appears on the left)
I haven't actually had anyone visit any of my sites who isn't using a browser that is not at least IE 4.0+, so I am not too worried about it.