You've seen the A+ pocket protector - cometh the hour for the full-size Pi version. Introducing PaintYourDragon's last-cut showpiece part ii: Adafruit Pi Protector for Raspberry Pi! It's not quite a full case, however it will keep your Pi B+ safe and svelte.
Keep your Raspberry Pi computer tidy and safe in this lovely clear acrylic enclosure. We designed this simple protector to be beautiful, easy to assemble and perfect for any use (but especially for those who want to carry their Pi around in their pocket!) This enclosure is only compatible with the Raspberry Pi 2, Raspberry Pi 3 Model B, and the Raspberry Pi 3 model B+. It does not fit the original Raspberry Pi 1.
The case is as minimal it gets coming in just two pieces of acrylic that secure with four screws. Made of crystal-clear acrylic, this case keeps the Pi secure. You can use all of the connectors on the edges of the Pi: HDMI, Audio/Video, microSD slot, micro USB power, and the four USB ports. There's also a cut out to allow a 40-pin IDC cable to the GPIO breakout pins on the Pi.