When do the SOLID principles become YAGNI?

As programmers we make trade-offs all the time, between complexity, maintainability, time to build and so forth. Amongst others, two of the smartest guidelines for making choices are in my mind the SOLID principles and YAGNI. If you don't need it; don't build it, and keep it clean.

Now for example, when I watch the dimecast series on SOLID, I see it starts out as a fairly simple program, and ends up as a pretty complex one (end yes complexity is also in the eye of the beholder), but it still makes me wonder: when do SOLID principles turn into something you don't need? All solid principles are ways of working that enable use to make changes at a later stage. But what if the problem to solve is a pretty simple one and it's a throwaway application, then what? Or are the SOLID principles something that always apply?

As asked in the comments: 


SOLID Principles
YAGNI


It's always difficult to judge an approach based on a screencast, since the problems picked for demos are typically so small that applying principles like SOLID quickly makes it look like the solution is completely overengineered.

I'd say SOLID principles are almost always useful. Once you become proficient with them, using them doesn't seem like something you have to deliberately think about. It just becomes natural. I've seen many throwaway one-off apps become more than that, so I'm now afraid of saying that I'm going to throw something away, because you just never know.

The approach I usually take is that if I'm writing a simple app for a particular task, I'll sometimes forgo big name principles in favour of a few lines of code that work. If I find that I'm coming back to that app to make further changes, I will take the time to make it SOLID (at least somewhat, since a 100% application of the principles is rarely feasible). 

In bigger apps, I start small and as the program evolves, I apply SOLID principles where possible. This way I don't attempt to design the whole thing upfront down to the last enum. That, to me, is the sweet spot where YAGNI and SOLID coexist.
