Here are basic TO-DO list and Tips of improving Web page performance with modern way (well, as of Nov. 2010...).
Well, at least jQuery
ASP.NET can use Ajax Control Toolkit
Basic page structure, "reset"YUI CSS Reset
The foundational YUI Reset CSS file removes and neutralizes the inconsistent default styling of HTML elements, creating a level playing field across A-grade browsers and providing a sound foundation upon which you can explicitly declare your intentions.
HTML5 - HTML5 Boilerplate
contains a very good essence of basic HTML/CSS structure.
Performance Check & TipsYUI Exceptional Performance
provide a Best Practices and tool (YSlow
Google Chrome also provide a developer tools
built in, which has a similar functionality as YSlow.
"Loading YUI: Seeds, Core, and Combo-handling
", by Eric Miraglia
The YUI Loader makes it possible to load all necessary YUI library just by one call. You don't need to include various dependent files by yourself.
Image LoadingYUI 2: ImageLoader
Loading images only when those are visible.
MS' tool: Microsoft Ajax Minifier 4.0
Yahoo's tool: YUI Compressor
CSS SpritesCSS Sprites: What They Are, Why They’re Cool, and How To Use Them
Instead of thousands of small images, combine them into one image, and use CSS to display necessary portion as icons.