Web2.0 is the common name for the ‘next generation’ of web-based products, services and businesses that leverage the platform independence and ubiquity of the Internet. Some would put more restriction on the definition referring to browser plug-ins like Macromedia Flash or specific web technologies like Ajax, but Web 2.0 is a concept that is independent of the technology it is built upon the same way that e-commerce is not a Java, PHP or Ruby dependant product.

If you’re looking for the leading edge of Internet programming, think about Web 2.0 products and services.

ProgrammableWeb.com has (beta) list of Web2.0 applications you can use right now.

Still interested in Web2.0? You’ll want to check out the 2005 Web 2.0 Conference

Petefreitag.com has a collection of cheat sheets for a variety of technologies. Split into 5 main categories - web, languages, database, version control and other. There are over 30 cheatsheets on languages like Java, JSP, Perl and Ruby. Web technologies like XHTML, CSS and JavaScript each have cheatsheets as well. The other category has cheatsheets for Linix, Vi, Google, mod_rewrite, htaccess, and windows commands among others.

Check them all out at http://www.petefreitag.com/item/455.cfm

link - O’Reilly Radar