I like to make espresso using one of these gadgets. When you press out all the water, it leaves a "puck" of compressed grounds, which you can pop out straight into the garbage or compost just by pushing on the handle. I was looking at the puck this morning and saw some lovely patterns made by different layers of grounds. One thin layer in the puck appeared more compressed than the other layers, but this more compact layer wasn't a straightforward horizontal cross section -- it had a ridged topography like one sees in the sedimentary rock hills around here. It made me wonder about the bulk properties of solid particles, about which I had seen an interesting presentation a few months before, on simulating such materials.
As I was holding the puck in my hand and examining this layer from all angles, the puck suddenly broke into its constituent coffee grounds and made a huge mess all over the floor. I realized then that I had fallen into the nerd's usual trap of neglecting practical matters for the sake of contemplating lovely abstractions ;-)