How to store a secret

I wanted to store one of my credentials online and was wondering about the secure way to do it. I wanted to store that info in my mailbox but if someone gets to my mailbox, I am done. Hence I was thinking of splitting the data and storing in 2 different mailboxes. I thought that it would be a good idea to split up and store data to ensure Security. This company called Cleversafe has actually implemented a more advanced version of the idea I had. Actually Adi Shamir (one of the co-author of RSA) had written a paper about this methodology in 1979. CleverSafe founder Chris Gladwin says that he was deeply influenced by Shamir's paper. What really impressed me was that you dont need all the split up chunks of data to get back the original message. For eg, say you split the data into 11 pieces. You only need 6 pieces to get back the original message. The Math(Polynomial Interpolation) behind this has been explained by Shamir in his paper. It is just a 2 page paper and is well worth reading.