Traditional thin film coatings are often optimized for durability, density and uniformity. However, recent opportunities for porous thin films have led to development of new techniques for fabrication of extremely porous coatings with precisely controlled microstructure. One such process is Glancing Angle deposition (GLAD), which combines the features of glancing incidence flux at the substrate with controlled substrate motion. Whereas "normal" evaporated or sputtered thin films usually possess a columnar structure that is densely packed, in the GLAD process extreme self shadowing from nuclei leads to greatly increased separation of columns and growth of isolated microstuctures. Microstructural shape may be tailored by substrate motion to produce, for example, helices, pillars, chevrons, and S-curves with feature sizes from 10 nm to 20 µm. In this manner GLAD has been utilized for simple one-step fabrication of films of high surface area and controlled porosity and structure from dielectric, semiconductor, metal, and alloy materials by sputtering, evaporation, and pulsed laser deposition. Although the stochastic nature of the deposition normally leads to random column nucleation, large area periodically arranged micropost or microhelix arrays may be easily created by deposition over patterned seeds on the substrate. This talk will present details of oblique deposition processes, characterization and description of film microstructures, and results of investigations or of opportunities for the use of engineered porous films in optics, thermal barriers, sensors, magnetics, and as high surface area devices.