So, not only is this my first CPG plugin, this is also my first forum post! Be gentle, please.
Sitemap Generator is a plugin that will create sitemaps for your Coppermine gallery with one click. First, a directory 'sitemaps' and a sitemap index file are created and then sitemaps for each category, which include links to each album and album item's page, are created. (Password protected albums are, of course, excluded.) I split up the sitemaps by category because Google accepts a maximum of 50,000 links in one sitemap and I have 60,000+ pictures on the CPG site I originally created this plugin for. Additionally, while looking through the PHP documentation, I noticed mention of users sometimes having trouble with file creation with PHP functions, so I added a panel which allows you to input FTP credentials for your gallery's server. The plugin handles the rest.
This plugin is inspired by Yoast's Wordpress SEO plugin which generates XML sitemaps. I used (and credited!) their stylesheet for the .xml files because 1) I think it's pretty and 2) I'm too lazy to rewrite it.
If you have any questions or run into any issues, please let me know through this topic or via PM. Also, if someone would like to create language files, that would be most awesome of you.