When do the SOLID principles become YAGNI.

As programmers we make trade-off's all the time, between complexity, maintainabillity, 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, dont build it and keep it clean.

Now for example when i watch the dimecast series on SOLID I see it start out as a fairly simple programm and ending up prettty complex (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 te make changes at a later stage. But what if the problem to solve is a pretty simple one and it's a through away application, than what ? Or are the SOLID principles something that apply always ?