An internship in a foreign country is an amazing experience. You can get work experience meanwhile traveling and discovering a new country and culture. It will not only teach you a lot for your professional life and be beneficial for your CV but you will also learn a lot for your personal life.
This depends a lot on your motives for going on an internship abroad. I personally recommend going on an internship abroad in one of the currently emerging countries or as I call them “countries of the future”. I always search for countries that have big economic growth and a big population and thus enormous potential for the future.
As always I recommend you stay as long as possible. If you can make it for six weeks, it's great. If you can even make it for three months, six months, or one year it's even better. The reason I always recommend staying as long as possible is that it takes some time to get used to a country (between three and six months). So the longer you stay, the more you will enjoy and feel at home.
AIESEC is exactly one of these organizations which promote an educational purpose as well as volunteering. It is the largest organization by young people for young people to gain experience abroad. You can participate if you are between 18 and 30 years old. AIESEC offers three programs in around 120 countries:
The program fee depends on your home country as they are the ones who will keep the money (and not your host country). AIESEC is a volunteer-based organization which means that most of the work is done by volunteers (searching for projects, accommodation, etc.). The program fee is used for seminars and other activities. Some programs have additional costs for the host country, host family, or the organization that is hosting you. In addition, you have to cover your flight, visa costs (if necessary), and health insurance. The good thing is that AIESEC is much cheaper than most volunteer organizations because as mentioned most work is done by volunteers and also because it has a lot of sponsors. Secondly, AIESEC gives you a discount for every further project you choose with them.
Also check out my articles on my AIESEC intership and Pakistan and my intership at the German Embassy in Brazil.