Use line weight and negative space or the density of local objects to reveal secondary images. You can use this to build layers within a logo to create a visual hierarchy. This element of discovery and surprise has value for the audience, and the difficulty of its execution will help to differentiate it and secure memorability.
The Faraday Project., Richard Baird, 2016, Techwear.
Tesori, Richard Baird, 2016, Linen.