I'm working on a Java library for parsing certain mapping-related files and I want to make sure it can handle as much of what people will throw at it as I can. Note that large chunks of the basic functionality are trivially portable to other languages, like C++, PHP, or Python. But I need sneaky files. Tricksy files. Evil files. ("And... Methodists!") .vmt Soundscapes Particle manifests .ent entity data from a BSP (can extract with GCFScape) Or any other file that TF2 uses with a similar structure. Edit: Never mind, that doesn't include VMFs... I'm not happy with the algorithm's performance for files that are thousands of times bigger than the ones I'm focused on. VMF parsing will be some separate project in the future, if at all. Put comments anywhere. Put comments that look like they aren't comments. Put some things in quotes and others without. See if you can do it all one one line, even. Don't worry about evil like "The VDC says it's a value from 0.0 to 1.0, but I'll put... TWO!", because that's not the kind of parsing being done. It's just turning the files into a bunch of nodes with key/value attributes and children. I will use them to create an unstoppably evil army of unit tests. The only rule is that they have to actually work in the game.