BBCWatcher writes: Can data be encrypted in a way that allows any calculation to be performed on the scrambled information without unscrambling it? It's a simple concept that sounds impossible, but if it were possible businesses and individuals could then protect their secrets yet still perform Web searches, medical studies, financial risk assessments, and many other tasks. Computer scientists call this idea "fully homomorphic encryption," and it was first envisioned 30 years ago by Ronald Rivest, one of RSA's coinventors. Rivest and two coauthors thought it was probably impossible. However, Craig Gentry at IBM Research recently discovered a solution, although at present the solution requires too much computing horsepower for common adoption. Nonetheless, Rivest now predicts the remaining engineering problems will be solved, yielding fully homomorphic encryption products and services. Crypto experts believe this breakthrough will make encryption much more convenient and more widespread.