I haven't checked the actual web-site as I don't use Photoshop, but I love the effect and can see me using this myself. Where I pinned it from said "How to Create a "Double Exposure" in Photoshop — Daily Epiphanie"
Double Exposure Profiles of People in Milan Combined With Buildings
Double Exposure Profiles of People in Milan Combined With Buildings by Francesco Paleari.
Portland-based photographer Sarah K. Byrne recently wrote and filmed a detailed tutorial on how to make multiple exposure photographs using a Cannon Mark III camera and accompanied the article with some great examples of her own work.