"Now that's an odd little plane . . . . "
Click here for video of the sighting of an armed Predator drone over Elgin, Illinois on May 12, 2012. (Talk show discussion here.)
Are there other reports of this type of drones over Illinois?
A database of drone sightings is being compiled at Dronespotter.org.
UPDATE: July 22, 2012
According to the Department of Defense Report to Congress on Future Unmanned Aircraft Systems Training, Operations, and Sustainability (April 2012), Illinois has two locations that have been designated as potential basing locations for unmanned aircraft systems (UAS) [i.e. drones] (p. 8 ff.): Lake Havana (for the RQ-7B Shadow) and Ipava (for the RQ-11B Raven).
It is disclosed that drones are operated at both locations under the status "Locations Requiring COAs [Certificate of Waiver or Authorization]". ("Locations where the Army currently conducts operations outside of Restricted Areas that require a COA from the FAA. In the majority of these locations, the purpose of the COA is to transition from the launch site to adjacent Restricted Areas. Additionally, the Raven can be operated using DoD-FAA agreed-to Class G airspace notification procedures for flights flown over Government-owned or -leased land." (p. 20))