If I'm doing a website, I end up with folders like "Controllers, Views, Models, Extensions, and Helpers". If I'm doing a DLL library I end up with folders reflecting the namespaces of my classes. If I write a desktop app, I end up with "Presentation and models" where models is subdivided further by namespaces.
My question is, where is a common place to put classes that aren't necessarily part of your logic or model?
For instance, if I find some code to convert XML to some arbitrary format, I usually put it in a static class and drop it in a folder called utilities. That's easy, but when I get into something that borders on domain logic that converts from XML into a domain specific language, where do I draw the line?
That's a pretty specific case, but I run into tons of these where I'm torn on putting it in the Utilities folder, the helpers folder etc. These are all folders I use, but hopefully the concept is clear, I just don't know how to organize my code when it isn't clear domain logic.