I am not sure if WAP (Wireless Application Protocol) is alive or dead. There are a lot of (more or less) usable WML (Wireless Markup Language) pages but there are more HTML pages optimized for mobile devices such as Pocket PC. There are also a lot of sub-domains (wap.example.com) which are no WAP/WML pages which can be confusing for users (and me).

WAP stands for "Wireless Access Protocol" and is loosely (and inaccurately) used to refer to devices (such a phones, PDA's, handhelds, etc.) that can access the internet. The confusion comes from the fact that Sprint phones have browsers that are compatible with multiple types of web pages, including WAP. A site compatible with your phone may be HTML, XHMTL, or WAP (i.e., WML). A "true" WAP site is a web site with pages written in WML rather than HTML. See similar questions...