X9

Love this approach! We used this method for awhile when conducting interviews, usually with a couple problems escalating in difficulty. Found it to be way more helpful to watch how someone troubleshoots than to test their aptitude with specific skills

I grabbed a short 2-letter Twitter handle within a few months after they launched. A few years ago I had someone used SIM hijacking to steal access to my phone number. This failed to get access to my Twitter account because I never set up a recovery phone number, however he got access to my Facebook and a few other accounts. I got T-Mobile to fix the SIM swap, but after 3 nights of harassment I just changed my handle. I didn't want to give in but the handle wasn't worth the trouble. On the plus side since Twitter doesn't allow handles that short anymore, once I changed my handle the hijacker's attempts were foiled.

Been also watching WheelTug[1] as a result of Andrew Tobias' interest (and investment) in it[2]. Sounds like they have more customers lined up, but competition already in this market should be a good thing!

[1] http://www.wheeltug.gi/

[2] http://andrewtobias.com/column/hot-brakes/

While it is largely based on the context of the job, I'd think some demonstration of fundamentals, like sorting (even if it's just bubble sort :-)), is important. It's another way to see which mental tools the candidate can use when debugging problems and they're forced to drill down through the layers of abstraction provided.

It might not need language level support, but anything to make it easier to leverage is a plus in my book. If the programmer doesn't have to concern themselves with extra parallelism-specific library calls and is still able to write a binary that can take advantage of multiple cores, that seems like a good idea to me.