Windows – /dev/zero equivalent in windows

What happens if you specify a count of blocks instead of manually interrupting it?

time dcfldd pattern="FF" of=/dev/hda bs=4096 count=102400; sync

then do

time dcfldd pattern="00" of=/dev/hda bs=4096 count=51200; sync

and compare the resulting times. Then look at the data on the disk to see if the boundary where ones change to zeros is where it ought to be (at about 200 Megabytes* for this example).

^{* That's real MB (1024*1024), not "maybe"-bytes.}

There's a "hacking" dongle out there that acts as a HID keyboard and can be programmed to act on events and send keypresses to a computer...

...but I fail to see how you get accountability or track-keeping with a physical artefact without some added personal knowledge like a password or a pin number or if it's truly one-use only. The stick could easily be lent, borrowed, copied and so on unless you personally watched over it and if the password was shared there's no accountability and no incentive to keep it private for any possessor.

If there's central user administration I'd just go with creating and handing out personal accounts for those who need them, separate administrative accounts as well (or grant the regular accounts the permissions needed when needed). You could then enable and disable them at will and with some decent-level speech about personal accountability they won't be shared as often as a stick.