There is no easy way to do it. Every different service would need another puzzle piece built to tie things together. This is the main reason that I only maintain my blog and gallery site, and most other items serve as links to that. This extends far beyond web space. Xbox Live, every forum, every instant messaging platform, things like netflix, all of these have friends or buddy lists that do not transfer. This is not even a programming question, but one of marketing and knowledge.

About the only thing I could think of that would serve to help this along and be a feasible solution is a way to parse sites that don’t have rss feeds into a more readable XML format. an HTML -> XML gatekeeper that would facilitate aggregation of sites or specific pages on sites that don’t have this abiilty.

A combination of a gui based html parser and manipulator, combined with a gui based xslt creation tool rolled up into something like friend feed, or at the least used to share user data could work, but would require a ton of maintenance. Users could manage the customized feeds, but moderators would have to maintain any updates. This looks a bit like what dataportability is trying to do but they’re still trying to gain cachet with devs so these things are implemented on the back end rather than brute forcing non-compliant sites by parsing and reorganizing data.

This doesn’t solve other issues though. If we want to share the movies we watch we would need a movie service like last.fm does for music. I find this electronic voyeurism really interesting… and honestly you’d be scared if you knew how much info I tracked on friends. Just remember that any time you want to run for president, I’ll require 10k bucks in order to keep my backup of your usenet posts from coming to light.