Cultural Vistas is a nonprofit based in the U.S. and Europe which is dedicated to increasing global exchange through a variety of programs (including the CBYX program which is designed to strengthen German-American relations). They offer 20+ exchange programs to help students and professionals from the U.S. and around the world gain global experience.
Programs include J-1 services, internships & fellowships, workshops, professional study tours, and seed grants. Since each sub-program has it's own eligibility and goals, you have to click around and read quite a bit to find programs for which you might be eligible.
Eligibility
Eligibility varies by program, but in general there are opportunities available to U.S. citizens, and for students from a variety of countries.