[Mike]

I use XHTML Strict, JavaScript, CSS and PHP. Images are very minimal, if they're used they are compressed beyond belief. Like somebody said, keep sites to a maximum of 770 pixels wide and no frames. I don't use flash, as it's too much of a bandwith eater. Tables are also slowly being thrown out, so start using divs people!

You should try to be accessible, always use alt text, don't specify your font in px use em, a percentage or a relative size (small, medium, large) instead. Try to not use graphics to display text, people with screen magnifiers will find it blurry.