What web design platform or software can I use to design websites like iGoogle or My Yahoo?

Posted by Website Building Editor on March 8, 2010 under Website Design | 5 Comments to Read

What web design platform or software can I use to design websites like iGoogle or My Yahoo i.e. websites (e.g.homepage) that can be modular in design and blocks can be moved around or replaced by the user? The user has a choice of modules to add to homepage and decides what to add or remove on their web page?