What are the valid use cases for client side encryption?

Question

I just read about the Stanford Javascript Crypto Library (jsfiddle example) which supports SHA256, AES, and other standard encryption schemes entirely in javascript. The librar

Answer 1

One use that comes to mind is host-proofing. That is where you want to store the data on the server or store and forward through the server but not give the server access to the data.

The client can encrypt the data prior to transmission to the server and keep the private key or at least the password for the private key locally.

I believe that this is the basis for services such as lastpass.