What should I learn next?

I'm just learning to program for a hobby.
I already have a weak foothold in C++, but I have done things like program Battleship and Yahtzee (with full GUI's) on my TI-83+, completely in BASIC.

What do you guys think I should learn next?
My friends have suggested perl and python.

>>7
Duck-typing, for example. If provided properly, the language crosses the line and becomes a high-level language.