Night Night is a network activity monitoring tool that will put your Mac to sleep when your network activity drops below a user defined threshold of network speed & inactive time. So the obvious benefit is you could start a late-night file download with an FTP, File Sharing, or any download client, knowing your Mac would sleep when the download was complete. Better yet, this program will work with any program on your Mac because it monitors network traffic from the operating system itself rather than just individual programs.
Their are two user defined settings to customize your network monitoring: "Speed Limit" & "Time Limit"
This setting customizes the threshold of network traffic below which Night Night decides your Mac is inactive and puts it to sleep. An added benefit here is there is no need to worry about network traffic momentarily dipping below your limit because Night Night uses a one-minute average traffic rate, so fluctuating network traffic will not trigger sleep. Conversely, by using a minimum here, rather than no network traffic, as the sleep trigger, Night Night allows your Mac to sleep even if an internet program continually pings a remote server to maintain a connection. A useful display shows the average network traffic rate over the past minute to help you determine what a good non-zero limit would be.
Rather than immediately putting your Mac to sleep when the network traffic falls below your speed limit, you can choose to have Night Night wait until network traffic has stayed below that limit for the duration of time you specify. This feature provides even more cushion for erratic connections, but it’s also useful if you have a Mac that acts as a file server and you want it to sleep only after you’ve finished transferring various batches of files. Another useful display here shows a timer with the amount of time that network traffic has been inactive below your set speed limit threshold.
For example, I configured the program to put my file-sharing MacPro to sleep after 30 minutes of low network traffic. The 30-minute time limit means that the Mac will not go to sleep immediately after a particular file transfer is done; instead, I get a 30-minute “grace period” to start copying any additional files.
There’s also an option to have Night Night start monitoring your network traffic only after your network data rate exceeds the speed limit. This is useful if you’re trying to download from a busy server: Night Night waits until your Internet program makes a connection and begins to download the desired file, and only then waits until that download completes to put your Mac to sleep. A sub-setting here lets you designate a time limit for giving up on the connection; for example, if the data-transfer rate doesn’t pass the speed limit after 20 minutes, Night Night can immediately put your Mac to sleep.
There are options to choose which network ports are monitored such as Ethernet, AirPort, and FireWire.
The user also has the option to monitor downloads, uploads, or a combined monitoring of uploads downloads.
Miscellaneous settings include: Start Activated, Keep Active After Sleep, and Before Sleep Quit the App.