What are alternatives to Replication to distibute data (Microsoft SQL Server) Is anyone knowledgeable of alternatives to SQL Server replication?

I have a scenario where separate databases will share a lot of the same data which complex queries will match against. 
We want to separate the databases out from each other (i.e. not on the same SQL Server) so we can ensure the server resources are not a bottleneck.

What techniques allow fast and efficient data sharing, fairly instantly.

Replication seems to be quite a slow and cumbersome technology?

Are there any new features in SQL 2012 and 2014 that cater for this kind of scenario?

AlwaysOn Availability groups doesnt quite cut it as these are readonly replicas.

I need a read/write replica where multiple data sources interact with each other

Server A        Server B      Server C

All have read/write transactions, all require as instant 
as possible sharing of data between them of the results of the transactions.


Thanks for your help
The reality is that SQL Server does not have a read-write scalability story in the same way that Oracle does in RAC so whatever you choose, you will always needing to consider that data-sets in one place or the other could be slightly behind. Availability Groups are probably the easiest solution to manage but then the only thing you are scaling out is readable replicas. Merge or Peer-peer replication probably provides much of what you need out of the box, but can be a bit of a headache especially in the wrong hands. You also need to think about avoiding conflicts.

I wouldn't attempt to roll out something yourself (i.e through SB or CDC) because this would ultimately become an administrative nightmare to manage in years to come and probably not provide you with richer functionality than is already provided.