I've been able to create XHTML Strict and CSS standards-compliant drop-down menus (with semantic markup) that work flawlessly in Firefox, Opera, Safari, and IE7
without Javascript. The only Javascript I needed was a helper file for Internet Explorer 6. :-/
Remember: don't use Javascript/AJAX just for the sake of using Javascript/AJAX. If it doesn't serve a useful purpose, then it's just a waste of bandwidth. I almost always stick to a maximum file size of 100 kilobytes per page; that number includes everything - the XHTML, CSS, Javascript,
and all of the images and graphics. That way, on fast Internet connections the page should load in under 1 second, while even on dial-up the page will still load in under 5-10 seconds.
