As a student or academic you may want to add another skill to your academic repertoire. You may want to read key texts in your discipline in the original. Such skills do come in handy in the most unexpected places (e.g. some of the earliest books and manuscripts on African languages were written in German by German missionaries). Philosophers, historians, scientists and engineers will find the rich sources available in German an important resource in their research. Law students find the study of German invaluable. Students of Religion and Theology will find that some of the most important sources in their areas are German. Researchers in nearly every discipline will benefit from direct access to German documents and resources. In Psychology and Medicine, important handbooks, texts and journals are written in German, important research is done in Germany, and a knowledge of German gives you access to sources you would otherwise miss, or get to know at a much later stage, when it has been translated into English.
You may want to become a teacher, a professional translator, or a journalist with access to a language and a culture besides English. You are interested in literature and want to expand your knowledge beyond the limits of your mother tongue. Or you may just simply want to encounter another culture to widen your horizon.
German is spoken in three countries with widely diverse cultural, political, and economic traditions: The Federal Republic of Germany, Austria, and Switzerland. Together with sizeable German-speaking minorities in Russia, Poland, the Czech Republic, Slovakia, Hungaria, and Namibia, there are more than a 100 million German speakers. German speaking communities can be found in Canada, the USA, all of the Latin-American countries, Australia and New Zealand. And then there are the millions all over the world who have learned German as a second or third language. Especially since the fall of the Berlin Wall in 1989, it is the single most important foreign language in Eastern Europe.
Over 11 million secondary school students in Eastern Europe are learning German as a second language, along with over 2 million university students, for a total of over 13 million current students of German!
In Western Europe German is the most popular foreign language after English. In Cameroon, German comes second after English, and in Nigeria 250.000 students study German.
Next to English, it is the most frequently used language in business, diplomacy, and tourism.
"For overseas consumption, it's good enough to communicate
in English". Nothing could be further from the truth. Any real interaction,
may it be commercial, political or academic is only possible on the basis
of a sound understanding of your partner, his or her language and culture.
Learning another language is never a waste of time. A foreign language
may be your most important tool! 
Thanks to the AATG: American Association of Teachers of German
MORE good reasons to learn German 1
MORE good reasons to learn German 2
Mark Himmelein's "Why Learn German?" Web Site
Visit Deutsch
im Netz: German on the Web
German
Interactive
And
Where is German spoken?