[Chalant]

I use this quite often for changing file extensions (rather than doing it one by one), as Linux is case-sensitive and some people don't keep consistent naming for assets some times, and it really started to get on my nerves.

Red is the extension the files have, green is it what you want to change it to. Of course, this can be used for anything, not just file extensions.

find . -name "*.DDS" -exec rename -v 's/\.DDS$/\.dds/i' {}