I can use a few bits and pieces from datacoin but don't want POW at all. Its under 20k to store a whole torrent file. Your standard magnet file and file name is less than 200bytes. If we set block time similar to datacoin and allow 100 uploads per block/minute we should expect a block size of around 20kb per block. Using his math that is around 10.5gb per year blockchain growth. That's 52million torrents uploaded per year.
I shouldn't need anything special like datacoin tho. All I really need is a coin with comments on the blockchain and I can incorporate that. Upload a file and it creates the magnet link. That magnet link, file name, and tipping public key are included in a comment on a tx and added to the blockchain. I do a sort and search in the wallet on the comments on the blockchain for what I want. I download the file and after the file is complete I'm given the option to tip. Once I press the button to tip a small amount of coins(a few satoshi) are sent to the pub key attached to that file. All coins sent to the public key are put up for stake in the next block round. There will be 2 seperate pub/priv key sets. One for sending regular transactions, the other is just for tips. There will be a very strict limit of how much can be sent as a tip and how often per pub key. I also have an idea of how to combat spam tips.