Acoc is one of my favorite *nix tools. It adds color to common commands like ls, diff, grep, make, and top. This drastically improves their usability. It’s also extensible, so it’s easy to color new programs and change colors for existing programs.
For example, acoc 0.7.1 includes rules for coloring unified format diffs. However, it doesn’t have a rule for “changed” lines, which start with ! and are unique to context format diffs. To color those lines, add this to your ~/.acoc.conf:
[diff,rcsdiff/t,cvs diff/t,p4 diff/t] /^([!*].*)/ yellow
This patch adds the rule to acoc 0.7.1.