$60 bucks a month turned out to be more than enough (in hindsight I'm a little troubled that it counted as being "frugal"). I didn't need the $50 extra I gave myself from a bet with my wife, because I ended up $76 to the good. Plus I put $50 into Kiva loans, got paid back on both, and put $25 back into another loan (meaning, in the end, that I'm actually $101 to the good).
This, I have to say, was a good discipline. In hindsight I can't believe how much I spent on gaming and hobby related materials in years previous. There are parts of this that genuinely have to deal with my just buying less and gaming with what I have more. It's also true that I've moved away, ever so slightly, from wargaming, et al, insofar as I am not building a Games Workshop army like I was a couple of years ago. I've also picked up some other non-wargaming/RPG hobbies, which do cost money and thus likely should be factored in the future.
But the real thing does have to do with curbing my "I'm depressed/stressed/had a bad day, let's go buy something" tendency, which makes me really happy.
So, let's keep this going, but maybe knock it down to $40 a month to just see how it goes.