Google OpenID URL

I’ve always thought that the URL for my Google OpenID were something like http://google.com/account/RaffaeleSgarro. Instead, it turns out that when a site request that URL to sign up (and in the case it doesn’t provide a Google icon), you can simply enter

https://www.google.com/accounts/o8/id

and it will redirect you to the Google server to confirm the authorization, and then back to the original site