1. "A mindfuck is a slang term which describes a work that uses literary devices such as nonlinear storytelling and plot twists in order to present convoluted, yet not conflicting, themes. A creation is usually considered a mindfuck when a casual observer is not able to discern the true meaning of a work without making a serious attempt to unravel the themes presented or when the plot is incredibly difficult to follow. Special examples of mindfucks involve a single plot twist which completely changes the viewer's understanding of the events in a film or novel as well as the ideas it presents." (Wikipedia
2. A technique in BDSM sex
where one person consents to something and recieves something completely different, and generally not harmful. For example, an individual agrees to be branded and is blindfolded, but in reality only touched with ice cubes.
1. "And with a bit of a mindfuck, you're into the time slip, and nothing can ever be the same..."
2. "A mental mindfuck can be nice."