You can't have an entire gang of Morkers riding around in the desert all day long without someplace to gas up their buggies when they get home, so I added a nice fuel tank to one section of my fort. I made the tank out of a tall, thin soda can, but since I'm pretty obsessed with making my terrain as durable as possible, I made sure to fill it with expanding foam before adding it to the fort. It's still not immune to getting dented, but it should be at least durable as the rest of the wall section.
I added plenty of pipes on the inside, mostly made from some kids' building sets. I actually went through a number of these sorts of sets before settling on this one (although a lot of terrain builders are big fans of this one), but the others had joints made from more bendable, rubber-like materials. Again, since durability is an important factor for me, I try to avoid bendable components that could flex and crack off their paint.
This section turned out really well and is certainly one of the more characterful sections of the fort so far. Excited to see how it looks all painted up.