Facebook and Google have both launched new user-ID services that let users take their existing log-ins and deploy them across a number of sites.

Google's Friend Connect, out now in beta, is pitched at webmasters who want to add social networking tools to their web sites. The search giant said in a blog posting that this is as simple as "cutting and pasting a bit of code", and requires no advanced coding or technical ability.

Friend Connect is also designed to be account-agnostic, letting users log in with an existing account from Google, Yahoo, AOL or OpenID, and other online sites including Plaxo and Google's Orkut.

"The goal is to facilitate an open social web," said Google product manager Mussie Shore in the blog post. "Using open standards like OpenID and OAuth, Friend Connect makes it simple for people to instantly interact with one another on the sites that they already love to visit. Additionally, web sites that use Friend Connect become OpenSocial containers capable of running applications created by the OpenSocial developer community."

Facebook Connect, meanwhile, which was announced this Summer, has also been updated, according to a blog posting on its web site. However, as might be expected with a social networking site, Facebook is asking its users to create momentum.

As with Google's service, Facebook Connect users can access different web sites using one log-in, meaning that they will not have to create new accounts as they move around the internet. The system will let users take their Facebook experience across a number of sites, creating links between them and essentially adding Web 2.0 features.

"For example, you can use Facebook Connect with the reviews web site Citysearch. You can easily log in using your Facebook account, and from there you'll be able to interact with all of your Facebook friends. They'll be able to see some of the same profile information they can see on Facebook, which is fully controlled by your privacy settings," wrote Facebook chief executive Mark Zuckerberg in the blog post.

"When you write a review for a restaurant, you'll have the option to publish that story back to Facebook where your friends can see it too. This makes finding your friends' reviews on Citysearch a snap. With Facebook Connect, it will be easier for you to share and connect with your friends across the web."

Zuckerberg claimed that Facebook will add sites to the service where there is user demand, and asked subscribers to get in contact with the firms in question to request a connection.