I participated in a DARPA brainstorming conference a number of years back. It was not paid, but a fun experience. So in addition to bidding on contract topics they propose, you can get invited onto working committees or symposiums and such (but that usually means you have expertise on the topic and someone involved knows who you are). It's a pretty good gov agency to work for as well from my various friends who have worked there.
What I worked on was more of a community of interest brainstorming conference where all the participants had an interest in seeing a good outcome of a DARPA program. You could call it "free ideas" but everyone knew that going in and it was the point after all. Research and development usually benefit from a free exchange of ideas from stake holders and people with expertise in the field (or adjacent fields).
Recruiting is never secret and DARPA, DoD, and the IC are just like the rest of the tech industry and _always_ looking for scarce talent (except they have to pay less than commercial sector thanks to congressional laws).
You seem to have convinced yourself of only negative interpretations as being options, but there really is a lot of overtly beneficial research done by DARPA and a lot of people who really believe in the good they do involved. Not to say that there isn't also occasional bad actors, bad policy, or mercenary transactions, but those are the exceptions, not the norm.
>>*You seem to have convinced yourself of only negative interpretations as being options, but there really is a lot of overtly beneficial research done by DARPA*
I appreciate your reality check on this - I dont exclusively focus on negative, but I am sensitive to efforts which ultimately result in negative (sociallogically - such as deeper surveillance) outcomes, and while darpa does awesome science, and great leaps in tech - every one of these steps /tend/ to feed surveillance-state paradigms.
