F#. Beautiful language, clean and concise, encourages functional programming without mandating it, type inference gives the benefits of static typing without the boilerplate. And it's a .Net language so you have the full .Net ecosystem, eliminating most of the disadvantages of using a minority language.

I am actually playing with F# quite a bit. It is definitely forcing me to rethink the way I am setting up my C# applications.

I really dug ocaml. I'm glad that F# has at least some actual usage out there.

Lua is pretty nice. Great memory footprint, easy to embed, and you can use LuaJIT if you want to trade extra memory usage for extra speed.

The best integration so far is probably Nginx:

https://blog.cloudflare.com/pushing-nginx-to-its-limit-with-...

We implemented Lua as the quest / NPC scripting language within a "C" based MUD engine and the performance has been incredible. Tens of thousands of individual programs and not a blip, game pulses smooth as ever 8 times a second.

I really like Rust.

I suppose its debatable whether it's unpopular, as Rust focused articles on HN tend to be up-voted. But, it does seem "unpopular" compared to Go, and other languages with a much larger following.

If popularity is not measured in the sheer amount of code written or programmers, then I would have to say Java. It has to be the most publicly shamed language. It's not really the language itself I enjoy. It's IntelliJ. Seriously, IntelliJ makes writing Java code insanely fast.

On HN, I'd say that PHP is the most public shamed language. IntelliJ makes Scala a breeze too.

I second the love for IntelliJ. It's amazing. It's almost like being telepathic - you think and the code appears on the screen.

And even Java... I've also had one problem made a fair amount simpler by Java's reflection, and a fair amount more simpler by Java's garbage collection. But I think Java is much to well-used to count as "unpopular".

> I'm specifically gearing this toward obscure languages -- in other words, not PHP and Java, because although nearly everybody hates those languages, nearly everybody knows them too. Languages with bad reputations that are no longer common count, though (like COBOL and FORTRAN).

(From the OP)

The latest version of Eclipse IDE (Luna) is actually quite good and possibly better than IntelliJ for Java development.

Have you used Intellij? It's quite possibly the best software development tool ever made. Sometimes I just gawk at how polished it is. Intellij IDEA is simply amazing.

Smalltalk - the granddaddy of all object oriented languages, and still the 'most' object oriented IMHO. And the only language that I know of that is typically implemented in a system that offers image based persistence, which is very cool (again IMHO).

Prolog. Extraordinarily simple model (you can implement an interpreter in a few hundred lines of code); yet extraordinarily powerful for solving many kinds of discrete-math (e.g. parsing, graph theory) problems.

Arc - the Lisp that runs Hacker News.

It's a really cleanly-designed language. While it has rough edges, the problems with it seem to be things it doesn't do, not things it does for confusing reasons.

Perl, unless you think it's still too popular to count. If not Perl, maybe 68000 assembler.

I wasn't sure whether to count perl. Ten years ago, I'd say perl fell into the same category as PHP and Java -- a large user base, many of whom dislike it. But, it's transitioning toward being a language of the past.

Perl probably counts.

For newer developers, I feel like even the linenoise/write once jokes are pretty much unknown. For an older set you still see one-liners and text heavy scripts, but no large players are really doing greenfield development in perl anymore.

Which is a bit of a shame, because perl 5.20 is a pretty far cry from the 5.8 I was using those 10 years ago...

Shen. Love it because it's small, easy to implement, nice to optimize and I have a real weakness for small implementations, Prolog and Lisp.

Edit: I really like Mercury [1] but the implementation is so crazy large and complex that I stopped pursuing it. While it's so lovely. I just try to use what I learnt from Mercury in optimising my Shen implementation.

[1] https://mercurylang.org/about.html

VBA. It's nice to be able to write somebody an excel macro that they can run without having to install anything. Sue me.

Brainfuck.

Because it's fun.

My favorite Brainfuck interpreters.

http://brainfuck.tk http://copy.sh/brainfuck/ http://www.iamcal.com/misc/bf_debug/

This is a good IDE for Brainfuck.

http://4mhz.de/bfdev.html

If you are interested, you can contribute to this Brainfuck compiler optimization project.

http://www.nayuki.io/page/optimizing-brainfuck-compiler

mathematica and/or the ＂wolfram language"

proprierary and slow (bad) but it has a huge, convenient, well documented standard library so it's convenient for prototyping stuff

plus it's really satisfying to implement complicated thing in a single line of code

CFML (language behind ColdFusion and open-source variants). Very approachable by beginners. Web console by default, no need to jack with config files. No database connection strings or convoluted models, just put SQL in <cfquery> and get a recordset. Simple data structure. Ease of HTML syntax, but power of c-like scripting if you want it. Backed by JVM, so can extend it in all the ways you'd imagine, and can also write extensions in CFML if you'd like. I do mostly Ruby these days, but I spent a long time doing CFML, so I'll always be fond of it.

I like PostScript. When you want absolute control over a vector image, it's the way to go, and if you set up your macros right (that is "procedures") it can be quite easy to modify and reuse.

I am burning a candle for Nim, formerly Nimrod. I like the brevity of the code I write using the language. I feel it has very few drawbacks, but I wish there were more of a community around it.

Mozart/Oz. Such a beautiful language and system; except the syntax, dynamic typing & sophomoric runtime ;-)

There is nothing like Oz. I spent 2 of my best years just studying its research papers.

During the programming languages course on Coursera they focused on SML for the first few weeks - while I haven't done too much with it outside of that course I really liked it

Agda; it marries formal mathematics and programming in a very satisfying way. I can't wait to see what comes of it and other intuitionistic type theory–based systems.

The most fun I had coding in recent years was writing a couple simple games to run on an Atari 2600 emulator. All kinds of hoops to jump through to get stuff on the screen, but somehow all the effort just made it more fun. I should do some more of that.

Solid intro tutorial here - http://www.atariage.com/2600/programming/2600_101/

Rexx - http://en.wikipedia.org/wiki/Rexx

Elixir, it combines Ruby-like syntactic sugar with Erlangs powerful OTP libraries and distributed systems mojo!

I will always have a soft spot for ActionScript - it's what got me into programming in the first place.

Haha, I scanned all the comments to see if someone said prolog just to figure out that the OP did :D

It's prolog for me too. Or I guess logic programming in general, but prolog is the main standalone one. I really hope clojure's core.logic takes off.

FoxBase+/Mac - so very versatile for an 80s database language.

JavaScript :)

(Just because a lot of people use it, doesn't make it popular!)

J is mind expanding.

So is datura.

Tcl

Mine's erlang.

Net.Data

Java