Right now I'm learning the Latin Language. I currently halfway through the first of the four books in the Cambridge Latin Course, meaning I'm essentially one eighth of the way through completing the course. I won't be posting comments in Latin anytime soon due to this. Before you go ahead, buy $50 worth of Latin textbooks and workbooks, study your brain out, and read Caesar in to original Latin, remember the following pros and cons: 
Pros:

• Latin is the basis for a large number of languages, including French, Spanish, Italian, Romanian Portuguese, and Maltese (I think). Knowing Latin facilitates the learning of the aforementioned languages, though if you want to learn any Slavic, Germanic or non-European languages you're out of luck.
• Several great authors wrote in Latin, such as Vergil, Julius Caesar, and Thomas Aquinas.
• It has been shown to boost SAT scores.
• There is some exceptional music written in Latin.
• Lingua Latina est optimus! (The Latin language is very good).

Cons:

• If you think that English grammar is confusing (which it is not), then Latin is not recommended for you. In my Latin textbook, there are tables upon tables upon tables showing the different forms of different nouns and verbs depending on their place in the sentence, whether they are plural or singular, and whether they belong to the first, second, or third declensions (nouns), or the first, second, third, or fourth conjugations.
• People might think you are a nerd, crazy, or have too much time on your hands.
• It does not have nearly as much practical application as some other languages.

Personally, I think that the pros outweigh the cons, but I'll let you be the judge of that.