> http://www.cs.umn.edu/Research/GroupLens/
>
> GroupLens(TM) Collaborative Recommendation
> Service
>
> The GroupLens Research Project will be provides the GroupLens
> Collaborative Recommendation System as a free service to the public.
> The GroupLens system provides personalized predictions of interest for
> every article you see in Internet newsgroups. These predictions allow
> you to quickly locate articles of interest and avoid uninteresting
> articles. Collaborative filtering techniques are used to generate
> predictions from the other readers' recommendations on article
> quality. Predictions are personalized by using recommendations from
> other readers who frequently agree with you. The GroupLens system will
> make reading Internet newsgroups productive again.
You could yourself choose S/N ratio.
-- LM lm+signature@sip.fi