**Name :** apcupsd
**Homepage : ** http://www.apcupsd.org/
**Why : ** I use this to monitor my UPS at work via USB, it's not the end of the world to not have it and can probably work around it but I'd like it added.
**Open source : ** Yes
**User : ** I can see a few making use of it, APC is a popular UPS and lots of people have them that I know.
**Link : ** https://sourceforge.net/projects/apcupsd/files/apcupsd%20-%20Stable/3.14.14/apcupsd-3.14.14.tar.gz/download