C, Perl, Python, Java and LISP — the dominant languages in open-source development. This list has changed over time, but slowly. Java bumped C++ off of it, and Python appears to be recruiting people who would otherwise gravitate to LISP (which used to be much more important than it is now). Smalltalk and Prolog are also popular in small but influential communities.
The Real Programmers who loved FORTRAN and assembler have pretty much all retired or died since 1990. Assembler is generally no longer considered interesting or appropriate for anything but HLL implementation, glue, and a few time-critical and hardware-specific uses in systems programs. FORTRAN occupies a shrinking niche in scientific programming.
Most hackers tend to frown on languages like Pascal and Ada, which don't give them the near-total freedom considered necessary for hacking (see bondage-and-discipline language), and to regard everything even remotely connected with COBOL or other traditional DP languages as a total and unmitigated loss.