I have implemented authentication systems for webapps several times over the years, but before I do it once more, I thought I'd ask if there's a canned solution I should know about.

Last time I checked, there was no built-in Rails authentication system and the standard solution was the [restful-authentication](http://github.com/technoweenie/restful-authentication/tree/master) plugin. Is that still the case? Or perhaps it's been folded into Rails itself by now? I've seen that happen.