SitemapGenerator enables Google Sitemaps to be easily generated for a Rails site as a rake task, using a simple ‘Rails Routes’-like DSL. Sounds pretty familiar right? (well except for the Routes-like DSL) But it’s not… it actually works the way you would expect. Plus it allows you to take care of familiar issues like: gzip of Sitemap files, variable priority of links, paging/sorting links (e.g. my_list?page=3), SSL host links (e.g. https:), Rails apps which are installed on a sub-path (e.g. example.com/blog_app/) and hidden ajax routes. As stated in the docs, it does have one shortcoming though - it only supports a maximum of 2.5 billion urls, after which you’re on your own.