Visualize CPU usage in your tmux status bar.
gcc -03 -o /usr/local/bin/tmux-cpu tmux-cpu.c
Then in ~/.tmux.conf:
set -g status-right "#(/usr/local/bin/tmux-cpu) #{pane_title} %H:%M %d-%b-%y"
set -g status-interval 1
Usage of each CPU core is visualised as a block in descending order. Example with 12 cores:
