Sometimes I have to pore over long debugging logs which have originally been written out to a terminal and marked up with colour or formatting via ANSI escape codes. The formatting definitely makes reading them easier, but I want to read them in Vim, rather than a terminal, and (out of the box) Vim doesn't render the formatting.
This makes viewing and navigating around multi-MiB console log files much nicer.
AnsiEscis old enough to have been distributed as a script, and then as a "vimball", an invention of the same author to make installing Vim scripts easier. It pre-dates the current fashion for plugins, but someone else has updated it and repackaged it as a plugin. I haven't tried that out.↩