There aren't any:) I doubt the others will ever come out anyway. Akasha is an ethereum project I think so will likely be delayed due to the ether war that is currently ongoing. The Synereo people seem really smart and talk a lot but have been doing that for over a year without anything useable to show.
I actually got reminded of https://www.yours.network yesterday, that might be comparable. though they haven't launched, so don't know too many details.
There aren't any:) I doubt the others will ever come out anyway. Akasha is an ethereum project I think so will likely be delayed due to the ether war that is currently ongoing. The Synereo people seem really smart and talk a lot but have been doing that for over a year without anything useable to show.
I actually got reminded of https://www.yours.network yesterday, that might be comparable. though they haven't launched, so don't know too many details.
first discovered it on Medium: https://medium.com/@McKie/how-yours-can-empower-creators-curators-from-all-over-the-web-3ae67d45c0e6#.2ve6ds50d
hasn't been any more news since May, though - so they may have missed the boat...