Partfinder Friday! The LM3914 is an analog-input LED driver
This is an oldie-but-goodie – the LM3914 is an analog-input LED driver. That means you can feed it an analog voltage input and it will light up LEDs in order, ideal for a no-microcontroller LED VU meter, or battery meter, or spectrum analyzer (when combined with some band-pass filters). Has nice extras like constant-current drive, and DIP size. I think these are rather cute!