Procrastination about social Networks during my vacation

"All the nerds have an account on Facebook, what about you ?"...
Ok I got one...

"All the geeks have an account on Twitter, what about you ?..."
Ok, I got one...

etc...

My favorite social network remains LinkedIn but I'm starting on being bored about all those social networks just because I cannot re-create another network elsewhere by sending again and again some invitations to my friends/contacts: they will definitely hate me :-). I don't remember where I read "I don't need a social network, the internet IS the network" but this could be true if anyone could host is own profile(foaf ? xml ?) in a file somewhere on the internet and a software could use it.

Some unordered ideas about this:

- use a kind of FOAF more structured/simple than RDF because I don't want anyone else to add a RDF statement about me.
- create a format for individuals, groups, jobs
- search by keywords ,dc:subject, location, degrees of separation
- cache the xml files in a cache on my computer (flat files ? javadb ?)
- implement a graphical tool and/or a command line tool
- trusted relations are bidirectional: he knows my mail (SHA1), I know his mail
- link to a picture
- location can be geo:lat/geo:long and/or name of country
- describe relationships (kind of relation, since...) instead of using foaf:knows
- include metadata about how long the file should be cached
- transform into rss to track the modifications.