WHAT LANGUAGE SHOULD I LEARN?

A little background: I took German for five years in middle/high school but have retained very little of it. I'd love to learn a new language this year and want suggestions (based on ease, usefulness, etc). I've downloaded Duolingo and I'm ready to go.
  1. Sign language!
    This was one of my favorite classes in college!
    Suggested by   @shaynaf
  2. I'm using Duolingo too! Learning Spanish & French
    Suggested by   @Deanndre
  3. Master German!
    And then if we get stationed in Germany I'll have a sexy tutor.
    Suggested by   @iammeghanmurray
  4. I'd say Spanish if you want usefulness but can you roll your R's? I can't.
    Suggested by   @justjills