DARPA has a long and storied history of funding ridiculous, crazy, and usually dangerous military inventions, all in the name of military defense. DARPA is essentially the government’s mad-scientist conservatory, where it tests out ideas like Matrix-style brain hacking and four-legged helicopters to see what actually works. But crazy as they may be, DARPA scientists don’t think up all of this shit on their own.

Once a year, DARPA’s Tactical Technology Office puts out a call for new ideas for its Proposer’s Fair, where everyone from private inventors or small businesses to major weapons companies can show off their plan for the next future-weapon. DARPA staff call the Proposer’s Fair “DARPA’s DARPA,” where ideas so crazy even DARPA hasn’t thought of them yet are encouraged (and this is the agency that’s trying to make gecko-skin climbing tools).

DARPA is highly interested in air technology like Aurora Flight Sciences’ VTOL X-Plane, waterborne tech like the Sea Hunter autonomous submarine-hunting warship, as well as social engineering projects, and electronic warfare techniques.

It’s also funded projects like robotic spy hummingbirds and synthetic blood, so it’ll be interesting to see what comes out of this year’s fair, though it’s difficult to figure out the origin of different DARPA projects during their development.

You can apply online for the Proposer’s Fair until 8 p.m. on March 25. The fair will happen April 20-21st.