What return? Dead people? Pollution? Fear?

Some notable ones off the top of my head include the Internet, GPS, computer mice (and basically the foundation of UI that uses them), onion routing, and prosthetic limbs.

Compare DARPA's $3B budget to e.g. the DoD's $650-700B budget. You can argue that either or both should be spending some portion of their budget on "the people" in a myriad of ways, but that argument gets way too close to personal politics for an engagement here to be worthwhile, IMO. Don't forget to vote!

With the exception of prosthetic limbs, so far those technologies have proven to be net negatives for humanity, only accelerating our suicide:

GPS: Nuclear missile guidance system

Internet: distributed nuclear missile command and control system

Computer mice: windows

Onion routing: fbi honeypot, enabled multiple violent insurgencies in northern africa and southwest asia.

And the list of actual successful darpa projects is longer than the one you provided, and the omissions are not nearly as benign as the ones you have cherry-picked.

And that's just what made it out of the lab. How many full ride college scholarships have they left on the cutting room floor? How many insulin shots? How many pounds of fresh food? C'mon man. DARPA makes war, not life.

I don't think those are very good examples. My internet must be defective. I haven't been able to launch a single nuclear missile from it.

Same for GPS-- compare the number of deaths from GPS guided nuclear missiles (0) to the number of lives saved by GPS (through more efficient farming, turn by turn directions, E911, etc)

DARPA has driven a lot of research in self-driving cars, space exploration, internet infrastructure (TOR for example), neural implants and so on. It's budget is also lower than some weapon systems that have never even gone into production.

I dislike the american military-industrial complex, but if I had to keep one thing from it it might be DARPA.

Lasers, fusion research, GPS, the internet...