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[This section discusses the potential of combining the ``perspective" offered by the Sun's height off the plane with very high resolution, multi-band observations like what's given here to map out the full skeleton of the Milky Way. Joao Alves will comment on extinction and Herschel-like emission maps. Jens Kauffmann will also add comments.]  In an ideal Universe, we would be able to travel far enough outside of the Milky Way to observe it from ``outside," the way that we see, for example, Andromeda. The story for years has gone that generating an observationally-based plan (overhead) view of the Milky Way is impossible, because we are ``in" the Plane. It is if Earth-bound astronomers have been living in the 2D world Edwin A. Abbott famously called `Flatland \citep{Abbott2008} when it comes to thinking about how to image the Milky Way's spiral structure. But, we can escape Flatland by realizing that the tiny offset of the Sun above the Milky Way's midplane gives can give  us a tiny, but useful, bit of perspective on the 3D structure of the Milky Way, and it can offer a (highly-foreshortened!) overhead view. This perspective is only useful when looking at very sharp, very narrow, features like Nessie, because puffier, more standard, arm-defining features will overlap too much to be separated in a very foreshortened view.  Carry out the following thought experiment. Draw a rough plan of a spiral galaxy on a piece of paper. Position a vantage point a tiny distance (a few hundredths of an inch) above that piece of paper, about two-thirds of the way out from the center of the galaxy. Now give the observer at that vantage point super-sharp eyesight and ask if the observer can separate the spiral arms arm features  you drew, as they observe them. They can! can--if and only if the spiral you drew has very narrow features defining its arms.  If the observer were exactly {\it in} the piece of paper (living in Flatland), separating the arms would be impossible. impossible, regardless of their width.  We are, like your observer, are at a tiny, tiny, elevation off of a spiral galaxy, and our visiion is good enough to separate its arms. very skinny arm-like features.  [CB NOTE  One piece of the argument isn't explicitly stated in this paragraph -- something as-confined-to-the-plane as Nessie is needed for this thought experiment to work. We have always been 20pc So, how might we use out vantage point  above the plane (and at least Plane to map out more of  the Galactic structure people have known Milky Way's skeleton? It turns out  that for Nessie is located in  a while), but this isn't place where seeing  a useful offset when most galactic features are substantially fuzzier/thicker than this. Put another way, very long IRDC projected parallel to  the interesting thing Galactic Plane should be just  about this paper the easiest, so it  is not surprising  that we are offset from found it first. Look again at Figure \ref{fig:topview}, and consider Nessie's placement there (the yellow-green line). According to the current (data-based cartoon) view of  the plane, Milky Way shown in Figure \ref{fig:topview}, Nessie is in the closest major spiral arm (Scutum-Centaurus) to us, along a direction toward,  but rather that not exactly toward, the (confusing) Galactic Center. Nessie's placement  there may exist galactic features which are substantially less dispersed means that it will have a bright background illumination as seen from futhrer out in the Galaxy (e.g.  from the plane than this offset] Sun), and that it will have a long extent on the Sky as compared with more distant or less perpendicular-to-our-line-of-sight objects.  So, how can we use out vantage point above the Plane to map out more of the Milky Way's skeleton? It turns out that Nessie is located in a place where seeing a very long IRDC projected parallel to the Galactic Plane should be just about the easiest, so it is not surprising that we found it first. Look again at Figure \ref{fig:topview}, and consider Nessie's placement there (the yellow-green line). According to the current (data-based cartoon) view of the Milky Way shown in Figure \ref{fig:topview}, Nessie is in the closest major spiral arm (Scutum-Centaurus) to us, along a direction toward, but not exactly toward, the (confusing) Galactic Center. Nessie's placement there means that it will have a bright background illumination as seen from futhrer out in the Galaxy (e.g. from the Sun), and that it will have a long extent on the Sky as compared with more distant or less perpendicular-to-our-line-of-sight objects. To find more `Nessies,' if such narrow features are in fact typical in spiral arms,  we need to be clever about where and how we look. Our current understanding of the Milky Way's spatial and velocity structure will allow us to draw more velocity-encoded lines like the ones shown in Figure \ref{fig:coloredlines} on the Sky, mapping out the whole Galaxy as seen from the Sun's vantage point. Once this drawing is done, we should design algorithms to look for dust clouds elongated (roughly) along those lines, and then we should examine the velocity structure of the elongated features, as we do in \S \ref{3D}, above. Of course, we need to be flexible in which features we accept as possible other ``bones," remembering that the model we will use to draw the expected features on the Sky is the same one we seek to refine! It is likely that a Bayesian approach, using the extant Milky Way model as a prior, will succeeed in this way. As extinction [xxJoaoxx] and dust emission [xx Tom R., Jensxx]data cover more and more of the sky at ever-improving resolution and sensitivity, we should be able to map more and more of the Milky Way's skeleton.