storing large string from browser

Hi,

I'm getting XML data from a plugin using client side Javascript and attempting to get it stored off on the server. My first attempt was updating the value of a hidden form field then storing it away in a model/table from the controller upon post/put. It turns out the data frequently takes up more than 65k of space. This is truncating my data due to row size limitations of MySQL.

I'm looking at Paperclip and CarrierWave as possible ways of storing the data, but I'm not sure if they are the best solution. I'm running into these two issues:

1) Both appear to want files. I'm not sure of the best way to handle this. Should I mimic a file/multipart form on the client or store the data to a temp file on the host in the controller before handing it off to Paperclip/CarrierWave to manage? (I'm not clear on the implementation details of either, though am more likely to figure out the temp file version quicker)

2) I need access restrictions and do not wish to place the files under public/. Is there an easy way to place it elsewhere, but still offer efficient use of resources for download?

BTW, I'm using Rails 3, MySQL, Linux/Apache/Passenger.

Thanks in advance, Mike