Bubblemon visualizes CPU + memory + IO load + battery charge as a bubbling liquid.
The water level indicates how much RAM memory is in use.
The color of the liquid indicates how much swap space is used, between blue (none) and red (all).
The amount of bubbles reflects the CPU load. Bubbles in the middle only means only one core is doing work. Bubbles across the whole width means all cores are busy.
A reed-like graph shows IO load.
Fog means your battery is running low.
curl https://raw.githubusercontent.com/walles/bubblemon/master/osx/install.sh | bash
Go here for development instructions for macOS.