WP Live php is wordPress plug- in by mbence that will automatically refresh your browser if you change any files in your theme or plugins directory.
This plugin was written to make WordPress theme and plugin developers’ life easier. Inspired by the brilliant live.js script (written by Martin Kool), this plugin will auto refresh your browser if you change any files in your wp-content/themes or plugins directories. No need for Alt-Tab and manual refresh anymore.
If you activate the WP Live Php plugin, it adds a small javascript file to your blog. It will monitor your directories by calling wp-live.php every second. If any file changed (i.e. has a newer filemtime), the browser will be refreshed.
The author says: You should never load this plugin on a live server! It is meant for developer environment only!
Download: http://wordpress.org/extend/plugins/wp-livephp/