Zoom-Meeting: https://wwu.zoom.us/j/97461739978 Abstract: Farrell?Jones pioneered a dynamic approach to K-theory computations of group rings. One of the tool they introduced are long-thin cell structures for flows on manifolds. Closely related are long thin covers of flows. I will discuss what they are, why they come up in K-theory of group rings, what we know about them and what I would like to know about them.