Looking at LPs, CDs, and DVDs with an electron microscope
An evening pause: This video is even more interesting than my title above, in that the guy making it used his electron microscope to make an animation showing what it looks like when a record needle is running through the tracks of a record. Most cool.
And since vinyl appears to actually be making a comeback, I think that even the younger members of my readership will know what a record is.
Hat tip Thomas Biggar.