Languages I love:
C: Very powerful, but elegant at the same time. You can do pretty much anything with it, but it's still fairly readable.
Common Lisp: There's something to be said for a consistent syntax, and no language's syntax is more consistent and elegant than that of Lisp. Add in some lambda expressions, higher-order functions, and reader macros, and you have a masterpiece of language design.
Fortran: I like anything retro, and as far as programming languages go, this is about as retro as you can get.
Javascript: I can have endless fun playing around with it. All the neat things it can do with a minimal amount of code makes it the perfect tool for the impatient.
PHP: See Javascript.
Ruby: It's consistent in its object-oriented approach and also has several neat functional features that are integral to the language.
sed, awk, troff, dc, make, etc.: The so-called "little languages" of Unix are quirky and unique, which makes them fascinating for us true geeks who like novelty.
TeX: Seriously, what's not to love about this language?
Languages I hate:
C++: C + bloat. Seriously, I have never seen anything quite so hideous as code written in C++.
Java: Forces you to use classes for literally everything, even things that are not even remotely object-oriented in nature, which tends to make certain programs intolerably tedious to write.
Perl: Combines features of several different languages, but not in an elegant way. Instead, Perl code tends to look like a confused mess of sed, awk, C code, and shell scripts haphazardly pasted together in the same file.
Languages I have a love-hate relationship with:
CSS: When it works, it results in beautifully formatted web pages. When it doesn't, it's frustrating as hell because it's nearly impossible to figure out why.