Most of the latest Nikon DSLRs allow for creating double or multiple exposures. My D300 will enable me to shoot up to to 9 shots on one file. Haven't tried this with my full frame D600 yet. Attached is a multiple exposure shot of Black-eyed Susans
Also comments about super-imposing 2 NEF files which again most of the latest Nikon's allow.
Share your thoughts and techniques