Some languages that are JVM specific today include Groovy, Scala and Clojure. I'm sure there are more. Beyond that, there is Jython and JRuby.
In addition, Java is a widely marketable skill. It's nice to be able to find work while you're a young programmer, even if it's boring stuff. People aren't always so fortunate as to be able to start a startup when they're young; sometimes they actually have to get a job doing crap work while they learn.
Or maybe even PHP? The problem with PHP normally is people jump in without any previous programming experience and say they have mastered it in 6 months - when in fact they know barely anything. You obviously have a good programming background and would use it properly.
If you want to go far in life, use words like "you" and "your", instead of things like "u" and "u r".
People will never focus on your linguistic skill for being correct, and they'll always secretly question your intelligence for using the latter.
i'm assuming that, by posting here, you're looking at web development. here are some languages useful for web dev: python, php, ruby, perl
if you're looking to expand yourself as a student and coder, consider looking into these: lisp, ocaml, prolog
if you want to graduate with a decent corporate job, take a look at these: java, pl/sql, cobol
What languages do you know more?
Id say go functional, entirely different, mindexpanding and might be very important in the near future because of concurrency/parallellism.
Erlang, Clojure, Common Lisp, Scheme.
For my entire development career, no matter what language I'm using, I've found myself using Perl on almost a weekly basis for little adhoc scripts. Generating test data? Text processing? Quickly automating some tedious task? Perl to the rescue. I guess if you know Ruby or Python you could do the same thing with those, but Perl is almost everywhere and you have all of CPAN at your finger tips.
Even though I'm not developing my applications in Perl I consider it one of my most crucial tools that I can't live without. I think every developer should have one of these and with its ubiquity and CPAN, a strong case can be made for Perl.
It also doesn't hurt that there are plenty of jobs out there for good Perl developers. We've all seen terrible Perl code and heard the jokes, but the fact is there are some very large Perl projects (some very high profile) being worked on by some smart people. Sure, Perl has its warts, but it's incredibly useful and a little discipline will go a long way.
There's my case for a practical language... If you want to learn something that will fundamentally change the way you think about programming then learn Lisp. I read the PG essays, the Eric Raymond stuff, etc. and decided to take a look. Eventually, things just clicked and it gave me a whole new perspective on the languages I already knew.
As for web language I love ruby (and rails as a framework) so I'm kind of bias but try learning python or ruby or if you feel like suffering (I find it too old school (I'm not trolling)) some perl (which as a huge community - CPAN).
Also, try looking at a functionnal language if you haven't in class (I learned Standard ML). It really helps to graps some concept that are harder to undertsand with `clunkier` languages.
I kinda went off track but hopefully this helps.
Given that you already know C and C++, I'd learn Perl, Python, or Ruby, since they're a very natural extension of C and C++ and can be used very easily in problem domains where you wouldn't want to use C or C++. Learning more than one of these may prove useful if you want to hack on a variety of different open source codebases, so whichever one you pick first isn't so important as picking one and having it in your toolbox.
As best I can tell Perl, Python, and Ruby are all practically equivalent. All equally suited to web development. Just pick one. I don't think it's unreasonable to claim that Perl is still the most likely to be professionally useful.
I never got the lisp propaganda. I invested some time with scheme and didn't get much out of it. Yes, I wrote macros and used call/cc. The most useful idioms are in fact already available and used in the so-called scripting languages. IMHO, your time is better spent completing good projects with rock solid libraries than futzing around with the language fetishists. Maybe there are some deep insights from Haskell I'm missing, but I seriously doubt it.