Helium hard drives revisited
In the article about use of helium in hard disks from Xyratex some aggressive change is offered. Helium is absolutely inert - it interacts neither with surface of platters nor other disk components.
Thus, if the disk is filled with helium, the protective platter covering can be made thinner or even completely omitted.
However, the side effect may arise: if the disk loses hermeticity and helium escapes, surface of platters will be oxidized quite quick and data will be lost. To kill a regular hard disk you need to open it and fill it with dust. For disk without protective covering it is enough to leave it without helium for a month. In this case it is impossible to put the disk aside and try to recover data from it, say, in a year.