I've got a community site that I built in Rails, and there's a forum kind of tacked on. It's really crappy and I hate supporting it, but some of the users really like it. Plus, it's not really core to what we do.<p>I'd like to just sign up for some kind of hosted solution that I redirect/CNAME a subdomain to. The only sticking point is that I really want single-sign-on (SSO), so that my users don't have to register new accounts or anything. Preferrably, I would just construct a link that has their user id, username, and userpic URL all hashed together into some parameter that I append to a special link. Then, when they go to the forums from my site, they're logged in automatically.<p>(Note: tenderapp.com does this for a ticketing system, and I like it a lot)<p>Any YC companies that do this? Anything else people can recommend?
Have you considered using OpenID, Facebook Connect, or both? Then you can support two-click account creation for anyone with a Yahoo, Google, MSN, or Facebook account. Check out Zoho and Plaxo's sign-up process for an example.<p>Also, HN uses Clickpass, which is an OpenID identity provider.