Just thinking about this, how expensive would it be to create a small, simple satellite, with solar cells, some large LiPoly batteries, a transponder and an EM drive that fires up every time there is enough juice in the batteries to run it for a few minutes?

Sticking with the 50nN thrust level for 50W of input and assuming that a 1kg LiPol battery has 260Whr available (https://en.wikipedia.org/wiki/Lithium_polymer_battery), that is approximately 5hr of running time and assuming that the satellite is 5kg, there will be a 10nm/s^2 acceleration.

5 hours is 18,000s so there should be a delta-V imparted on the satellite of 1.8(10^-4)m/s which is tiny (I did say this is a pretty useless drive at the current time right now) but should be measurable or at least noticeable to its relative position to a control satellite that was launched along with it.

This is really amazing and hopefully it is turning into a window into parts of our universe that we've never imagined.

But, reading the articles, I think we're a long way off from understanding what this phenomena is and how to exploit it practically. Going back over the previous articles, the measured force was for 50 uN from 50W of power - this doesn't seem like a very practical application as yet; the claims of round trips to Mars in less than a year are very exaggerated.

On that point, I thought we could go to Mars in 3 months or so now; it just takes a nuclear rocket rather than chemical, plasma or EM drives.

Finally, in the hacked.com article, rather than expelling "propellant", aren't you expelling "reaction mass"?

I'm not at all arguing that point. I don't even particularly care one way or the other. I'm more fascinated that everyone is so busy arguing over over everything other than this blatant leveraging of the situation.

Hear me out. I'm saying that if they wanted to arrest the kid, they would. They're intentionally publicly saying 'Gee, nothing we can do about this! If only we had some new laws for this new technology...'. I guarantee if they weren't playing that angle they'd just arrest him regardless of whether a crime has been committed or not as people got up in arms about the whole thing. This is an opportunistic play for more resources the way I'm seeing it.

That would be very reasonable. I'm very sure it also doesn't allow a new large budget to be appropriated and I almost guarantee the police are actually looking for new toys and less restrictions along with a bigger budget. I'd bet you a beer my interpretation is much closer to what you're going to see if the recent pattern holds. I am pretty sure of this: that quote wasn't an off the cuff remark; it clearly was a call for action while giving the preferred solution in a thinly veiled way.

OTOH, I'll be the first to admit that I very well could be wrong. We'll see how it plays out.

They're intentionally not finding a reason to arrest him and they tell you why right there. They want new laws. This is an underhanded attempt at manipulating the public and I very much suspect it will work if the comments on this story are any indication.

Good point. Can I say simply that I believe that once something is over, it should stay that way?

I say this as someone that runs ZFS on his backup/file server; if you do have to restore or resilver it can take a long while! A single slow drive in a vdev will limit the entire pool's IO (the extent of which is entirely dependent on topology, but the weakest link always crushes you in ZFS). After a handful of TB of data, even with a pool of mirrored vdevs and a flash cache device, the resilver for a single drive can take a day unless you've got some serious spindle count at high RPMs. Even SAS drives don't provide that many IOPS.