In my opinion, Smashthestack's Logic wargames are a lot more buffer overflow focused than IO ones. The first level php problem is rather misleading in that regard.
Smashthestack and overthewire both have a wide variety of wargames that might be fun to look into if you're interested in pursing security related challenges:
Don't understand why this wouldn't just been merged into the upcoming versions of R. Creating a new project is strange, anyone know as to why they might have done this? Sure there's probably a good reason that I'm just unaware of.
Solid intro into the lambda calculus. Wasn't so into the js examples, but after reading the other comments, I can totally see how a functional/mathematical syntax would have been very disorienting for someone not familiar with the lambda calc. Since those people are obviously the target audience, js seems fitting.
Washington creeping up on that third place spot. Not surprising considering all the northwestern tech companies. Wouldn't be surprised if wa ranked second or third for tech people/total population.
Smashthestack and overthewire both have a wide variety of wargames that might be fun to look into if you're interested in pursing security related challenges:
smashthestack - http://www.smashthestack.org/ overthewire - http://www.overthewire.org/wargames/
There's also an intro level CTF going on for another 9 days @ http://zeromutarts.de/
Registration is easy and instantaneous.