With my "must try all the things" geek hat on, when I saw a thing called RetroShare mentioned, I had to download it and give it a try. Or more accurately, when I read the wikipedia page for retroshare, I had to download it and give it a try.

So far, it looks good. If it delivers everything the wiki page says it does, then I like it. As far as I can tell though, there are even fewer people using it than there are using Diaspora*, and that isn't exactly flush with users at the moment. (NB - that may just be that I haven't managed to find the right circle of people to get in with, I recall the early days of twitter were similar, and I struggled to get up to following twenty or thirty people, and I now follow, erm, well over seven hundred.)

Apparently this link should allow you to add me as a friend on there, but I'm guessing that depends on if your browser knows what to do with a retroshare:// link or not. If not, here's my public key

-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.4.9 (Darwin)

mQENBE8xrUwBCADMV5YyaI8AGiVErQozR6w5DRQOHt8CIv5LCOTqJQcYusIyJiW8
RdhequZn/Id2FA2AmLSjew7brnQ4jfJzBcia3LseXeouaEZuEh0ZIPd3XmqWRZrW
z/NDPax06qZp+apfRVUxsd8Gd2/mBfh+gRbRjFZV9oUuCDxg0vo3eMvFngcrZrXh
1/gAOK4rwRoDfTcvGKMGniiKbZS53jR+yhTrc7hlm3X0t+lFk28F3tdFldGc3hqy
o2d5hf+0xONhZ7rqCvSW7nR2uWhP2mZfGt8B6qv5Wh56b3wyXsI5ub2cjR+bVAiZ
+3o9WvzPi+7Pi8DF6HrBGXBsAEjuGTiSLBWjABEBAAG0RU1hdCBTdGFjZSAoZ2Vu
ZXJhdGVkIGJ5IFJldHJvc2hhcmUpIDxlbWFpbCtyZXRyb3NoYXJlQG1hdHN0YWNl
Lm1lLnVrPokBNgQTAQIAIAUCTzGtTAIbLwYLCQgHAwIEFQIIAwQWAgMBAh4BAheA
AAoJEC8Dkozy5Z+Z7UUIAIcnJ09d6uerCWWHgr8C7XrcHbnx87AwCjpwiKF/ezxK
o3WrDNnyGBc/LJn7ZmY69PVTuYp5L+8mX4Wx2BzpE8VLzfpvG+0Mr3ERdRIkof37
uY2vuNL2LJ9HeaA2X6dEMeaQo1lH78kXbrbgcrwKtL0GmUWtAkHCDmgUl56ZVqE8
UkwnlluG3MWnx4dmTlZK8w5fKQLCHnf0xcb0kOGaCXjHrBlYetw+0UnCX49ZUJZw
hLdG9ZBAFjbSGN4c/JapJseChENRIPLCuNaYMXyYMS0E9IvdcZIlmVA6du+DjfIN
vg1VcuJOorIjsFgfq1mVHXTzro/P1JQUXdJhE3ZB4i4=
=VwXS
-----END PGP PUBLIC KEY BLOCK-----
--SSLID--bd6cbc71a291c70de9a167621205f664;--LOCATION--MBP;
--LOCAL--192.168.168.206:22901;--EXT--94.195.123.152:22901;

Apparently you add this, then send me your public key, then we're connected and can chat/message/share files/various other things in a full on decentralised way. I'm not sure how it copes with machines that are not on full time - I assume that when you're using it on a laptop/home desktop that is rarely on, it is somewhat like ships passing in the night.

Now if only I could find someone else who is using it to test that assumption.