Fuji 14mm f2.8
The 14mm f2.8 is a lens that has been on my camera far more often than I expected when I purchased it. It's quick and light and images have minimal distortion. I've found myself shooting both landscapes and portraits with this lens. One great thing about shooting portraits with a wide lens like this is that it forces you to get up close to your subject.
This lens comes with me pretty much every time I take my camera out. It's great for group shots or working in tight spaces.