[super3]

I'd take a look at some of my writings for meta transactions and templates here: https://github.com/Storj/Metadisk/wiki

Bitcoin only supports up to 80 byte of data per transaction, our model uses 1 kb or more, which makes unusable for our current platform. We are not creating another cryptocurrency just for the sake of doing so. There are many technical reasons why we can't do this yet.

So we already have a long term plan to implement sidechains or treechains. Currently this is only concept/vaporware, so we are not waiting around until it happens.

[deftnerd]

I'm writing a system for my OpenID provider servicewith background checks (blockauth.com - BitAngels.co backed project launching in 20 days) that has to store a lot of data in a decentralized system.

Since MaidSafe and all the others don't have a working product yet, I've had to make my own system. Each user is assigned a transaction ID and the 80 bytes on the blockchain simply store a DHT hash for the document, so the system can download the encrypted user dossier through bittorrent. It's working pretty well so far.

The system isn't able to pay users for helping seed the file, but all of the franchised Identity Registrars that'll use my system will be required by contract to seed all of those files.

It doesn't totally solve your problem, but 80 bytes is enough space for a DHT hash and that might be helpful.