Roland Rust

Prints out your webservers php settings as well as other information about your WordPress installation. 
Important for posting at various WordPress support forums.

Phpinfo

Prints out your webservers php settings as well as other information about your WordPress installation.

Dejan Batanjac

Simple WordPress plugin that displays exactly the same info as phpinfo() function and nothing more, in the classic presentation (see the screenshots). 
Basically the smallest peace of code you can imagine.

PHPINFO Print

Displays web server information in a traditional way just like phpinfo() function

Phpinfo vs PHPINFO Print