flattenArray(array) -- flattens a hierarchy of NSArrays (should be a category I guess) [reason https://twitter.com/ikenndac/status/63609670182502400 -- but not a oneliner]

gistfile1.m

NSArray *flattenArray(NSArray *arr) {
    NSMutableArray *collector = [NSMutableArray array];
    for (id obj in arr) {
        if ([obj isKindOfClass:[NSArray class]]) 
            [collector addObjectsFromArray:flattenArray(obj)];
        else 
            [collector addObject:obj];
    }
    return collector;
}