Paper note 0.4.3 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The program is included in Productivity Tools. The actual developer of this free software for Mac is Mark Cornelisse.
From the developer:
This app provides you with the ability to send paper notes, so you can have a private chat in any environment: classroom, public presentation, or even in public transport. The special part is that it doesn't require a Wi-Fi hotspot or any Internet connection. Paper note will just find Macs nearby running Paper note as long as you have Bluetooth and Wi-Fi enabled and they are within each other's Wi-Fi range.
You may want to check out more Mac applications, such as World Record Paper Airplanes, Papa Penguin or Paper World - Spot The Differences, which might be related to Paper note.