So you're saying Hackathon was H@X0R3D?
"Covert acoustical mesh networks"?!? Housewives invented this thousands of years ago, only back then they called it "gossip."
I guess we need to send our letters in holographic envelopes that can only be read at an angle. Straight on, it just looks blank... or maybe a big finger. And that's probably what the camera will record.
But what is the carbon footprint of all this electricity that Earth is using? Surely that can't be good. We need a treaty with the other planets that curtails Earth's inordinate use of the universe's electricity! Why, it just might throw the interstellar ecosystem out of balance unless we get it under control!
Apparently that knowledge didn't include the fact that A LOT is two words.
Maybe that B.A. in History isn't such a bad degree to have after all. Now all you need to do is convince corporations they need to have a history department to manage all of their documentation in such a way that it is discoverable and accessible.
One of my favorite lines is, "Your data is secure. We just can't access it." In other words, if you are going to use a particular medium as an archive, you need to ensure that the data can be read from that medium, in perpetuity. If the technology is in danger of becoming obsolete, the archived data must be moved forward to new media.
Of course, that isn't enough. The data must be indexed in such a way that the information you need can be found. Finding a needle in a haystack is easy with modern technology; finding a hand-drawn flow chart explaining how a particular "black box" in your manufacturing plant converts X to Y (and why it's painted blue) among hundreds of thousands of pages of poorly indexed documentation is exceedingly difficult.
You may want to consult a lawyer, but in negotiating with the former company, you could demand that you be exonerated from violating company policy during your employment in return for supplying any corporate documentation you may discover in your possession. How did your employment contract and employee policy read, and are you past any statute of limitations regarding possession of IP during your period of employment? Considering what a jumble their documentation is in, could they even find a copy of your employment contract and employee policy that was in effect during your employment? If not, then would they be able to present a valid breach of contract case without producing the contract?
Also, considering that nature of this project, you aren't an ordinary outside consultant supplying new information or engineering of a subset of the plant, but rather a former employee recreating holistic institutional intellectual property on a contract basis. Therefore you should be granted employee-level clearance to access and discuss all current intellectual property as it relates to the project.
As far as personally retaining documents related to corporate operations, much of the information contained therein may be of your own design. This intellectual property, while legally the property of the corporation, is also your personal idea. The non-compete clause in many employment contracts implies that you cannot use the ideas you had while employed at another employer for a certain length of time, but once that time is passed you should be able to reuse those ideas. Therefore you should be able to retain at least that portion of intellectual property that is your creation; it may be best legally to recreate the rest from memory.
As an employee of a contract IT consulting firm, I retain copies of network documentation for many of my clients on my personal laptop. (My company does not supply computers to its employees, rather it is a Bring Your Own Device type of workplace.) I am not aware that I am in violation of any NDA by this, but it would be terribly inefficient if I could only keep such information in repositories under the control of each client. If a client requests documentation of their network that I have in my possession, I will provide it to them, charging only for any necessary modification to reflect current configurations. After all, it is THEIR intellectual property, which I have previously sold to them by charging for the time previously spent creating the documents.
Will I destroy this information when the client ceases to become a client, or when my employment is terminated? Probably not. Chances are, I'll archive it and give a copy of the archive media to my employer. I may keep an archive copy myself, since I don't trust my employer to be able to find the archive somewhere down the road. Shoot, I don't even trust MYSELF to find the archive, but the more copies there are floating around, the better the chances of finding it when needed. Of course, that means the chances of it falling into the wrong hands and becoming a tool of corporate espionage is greater as well.