Mike Jolley (a11n)

Testing your WordPress site? This plugin allows you to display memory, page load time and query count in the footer of your site on both the front-end and within admin.
This plugin is partly based upon the WP Query Counter by Steven Word (http://www.stevenword.com/plugins/wp-query-counter/) and has been customised for my testing needs.
If you’d like to contribute to the plugin you can find it on GitHub: <a href="https://github.com/mikejolley/WP-Page-Load-Stats" rel="nofollow ugc">https://github.com/mikejolley/WP-Page-Load-Stats</a>

WP Page Load Stats

Not sure why this only has 100+ users but this is a great tool!

Excellent!

Display memory, page load time, average load time and query count in the footer of your site.

Sergey Biryukov

Creates a separate tiny .mo file to use on a site front-end. Allows to save some amount of RAM on a shared hosting server.
Thanks to MAX for the original non-plugin solution and to AlexPTS for the idea.

WPLANG Lite

Creates a separate tiny .mo file to use on a site front-end.

WP Page Load Stats vs WPLANG Lite