I can't say I've ever even tried to put that much data into memory at once, but I have dealt with some large collections. You might try chunking up the original data and storing it in temporary tables you can iterate through so you have less to work with at one time. If your database provides something like LOAD DATA INFILE, you can make use of it to dramatically reduce transaction times when it's time to put all the data back.

That all said, if it were mine to do the single word that would keep me awake at night is "cluster".

Good luck and have fun with it!