See the demo: http://www.3solarmasses.com/retriever-bootstrap/
This theme gives bootstrap a new menu with a stich background, a new well design and new fonts. The theme is only 60 lines of CSS so it doesn't get in your way.
Just download the zip and include retriever.css after bootstrap.css (and after bootstrap-responsive if you want it to be responsive). You will also need the stich.png image for the header.
For a fixed header navbar, be sure to include an 80px padding at the top of your document. To change to a static navbar, just change "navbar-fixed-top" to "navbar-static-top" and alter the top padding to around 20px.