[Sean1708]

From the paper:

> For 1Tb device the estimated mass change is 2.5 × 10^-25 Kg.

I don't actually know how precise we're currently able to measure mass, though.

[trentlott]

A proton weighs ~10^-27 kg, so that's about 100 protons. I sincerely doubt we have masses that are quite that good - especially that which can take a high mass item (harddrive) and detect an atomic-scale change without being hideously noisy