This is a highly customizable implementation of Subpixel Morphological Antialiasing for Unity3D.
Tested with Unity 5+ (Personal or Pro). Works with the deferred & forward rendering paths, in gamma or linear color space, with Directx 9, Directx 11 and OpenGL targets.
It comes with a few quality presets but you can easily build your own in the inspector. Every inspector setting comes with a help popup so you shouldn't have to dig into the (documented) source code.
Right now it implements SMAA 1x (+ predication). Implementing Temporal SMAA (T2x) should be doable, but the spatial (S2x) and spatial + temporal (4x) variants aren't possible in Unity right now.
Comparison screenshots with FXAA and Supersampling.
Drop the SMAA folder in your project and add the SMAA script to your camera (or select your camera and use Component -> Image Effects -> Subpixel Morphological Antialiasing). The effect should be the first in the post-processing chain (before Bloom, Tonemapping, DoF etc) or it will miss some edges, especially when working in HDR.
An updated version of this effect is available in Unity's official Cinematic Image Effects repository (Unity 5.3+ only).
Zlib (see License.txt)