The Grumman X-29 was an experimental aircraft that tested a forward-swept wing, canard control surfaces, and other novel aircraft technologies. The aerodynamic instability of this arrangement increased agility but required the use of computerized fly-by-wire control. Composite materials were used to control the aeroelastic divergent twisting experienced by forward-swept wings, also reducing the weight. Developed by Grumman, the X-29 first flew in 1984 and two X-29s were flight tested over the next decade.
Source: Wikipedia, "Grumman X-29", available under the CC-BY-SA License.