During the last three years, the research on metamaterials in Bogota has been focused on passive metasurfaces design from microwaves to optics. In this talk I will shortly present the following seven ideas developed in this period: 1) Theoretical Constraints on Reflection and Transmission through Metasurfaces; 2) Linear to Circular Polarization Converters Based on Self-Complementary Metasurfaces; 3) Duality for 3D Metamaterial Resonators?; 4) Metasurfaces for Angular Filtering and Beam Scanning; 5) Waveguide Bandpass Filters made of Thick Complementary Small Resonators; 6) Experimental Demonstration of the Saturation of Nanoscaled SRR and CSRR; 7) Plasmonic Complementarity Theorem.