An apparent example of AnComs kicking ass and taking names is the PKK and YPG serving as a private security force/free militia in the areas of the middle east being outright destroyed by the Turkish government and ISIS. Information coming out of that region is sparse and incomplete, which shouldn't be surprising given the governments' propensity for murdering journalists on live TV.
I've been watching the PKK (Kurdistan Workers' Party) as closely as I can, especially the YPG (Peoples' Defense Units) for the last couple years. On rare occasion, they will appear in mainstream news, but never by name. When one hears of all-female Kurdish units racking up hundreds of confirmed ISIS kills on Fox News, that's the YPG.
They PKK (as one could guess from it's name) has a checkered past, to say the least. Having originally been a straight-up communist revolution group, they have since reformed into an federated voluntary anarchist community... which still sounds very communist. It's hard to argue with results, though. Where the PKK and YPG fight, civilian casualties drop dramatically, important tactical positions against the local governments (Turkey and ISIS, primarily) are secured, and quality of life improves while crime rates drop. Or, so the information coming out of the region seems to indicate.
Today's resource suggestion is the YPG Wikipedia page. The information on the page is too sparse to have much of a political spin, but it provides enough information to begin a journey down the rabbit-hole. I have done my best to not simply sing the praises of the PKK and lay all the supposed facts that I have found out on the table, as there is simultaneously a paucity of facts and a surplus of speculation. If one could read the local languages, I'm sure they would be able to put together a more complete picture than I. If someone is genuinely concerned about ISIS (I'm not) and wants to know "How would anarchists stop things like ISIS?" I recommend looking at the YPG for answers. It would seem to be one of a handful of real-world examples of anarchism working better than statism when it comes to dealing with aggressive government invasions, but you have to figure out what you think about them on your own.