One thing about getting something like a Haskell job that's rarely mentioned is it seems like it's very much an all-or-nothing proposition. Casual or intermediate dabblers who like learning new things like Haskell but aren't total wizards get no points.<p>A lot of the investment bank openings for functional programmers want someone who's doing a PhD in programming languages, from what I've seen, for example.
I think it's more that people who program in $OBSCURE_LANGUAGE are much more likely to have picked up that language out of interest, rather than from wanting to have a cushy, decent-paying desk job.
I wouldn't say that just because someone knows Haskell they are suddenly a good programmer. Some schools use Haskell for their intro programming classes nowadays.
That, I am sorry, is an inefficient filter. I used at one point believe anyone who didn't know C++ wasn't a good programmer until I met a few people who wrote applications in languages like VB and they were as good as C++ developer would have done.<p>There are other ways to filter out résumés. Within 10 minutes into a phone interview you can eliminate quite a lot of applicants and I for now just stop the interview at that point. Once someone makes it through the phone interview you are pretty much left with a good bunch of résumé to pick from for the next round.