So far I have looked into multiple apps, such as AirDisplay, Splashtop, WIDisplay, Synergy, and ScreenRecycler as mentioned by bwall's answer. The goal is this: just like you could extend the display of a Mac to a monitor using Thunderbolt, I would like to extend it to a Windows 10 screen using some software. – Suleiman Aug 6 '16 at 18:36. ScreenRecycler is a Mac application that lets you use a second computer, whether it's a Mac or PC, to extend your computer's screen. The connection between the two computers is done with a VNC client over a local network. If the other computer is a Mac, ScreenRecycler includes.

Using a Mac as a screen is a neat capability, but a horrible waste of electricity.
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EMOJO: mojo no longer workin'

Waste is defined as spending something purposelessly. If gaining the extra screen increases your productivity or adds value to your work, then spending money for a new monitor would be the waste, and the electricity spent is actually a worthwhile use of that resource.
Of course, I know what you meant, but I refuse to participate in your guilt.

If I see this correctly, this would allow me to have more than one external screen with a laptop?

Ipad Mac Mini Display

You can also use it to have a pseudo second screen on a Mac Mini that is running a TV as a media centre. It's not quite perfect, but means you can do stuff on that machine without interrupting what's showing on the TV.

Screenrecycler Macbook

Well, TightVNC (installed on a PC) is unable to connect to my Mac (where Screenrecyler is running). I've tried changing the ports from the default 6900 to 7900, no change. The Mac can initiate a RDC session on the PC, so I know they can connect to each other. On the Mac, ScreenRecyler is listed in the Firewall as exempted application.
There might still be a firewall on the PC preventing the connection, but I have no idea how to check this. Or there are some settings in TightVNC that I would have to change for this.

Switching the port in Screenrecycler to 5900 made it work (I had tried to set the port in TightVNC to 6900 but apparently that did not stick).

At a Glance

Expert’s Rating

Our Verdict

Editor’s note: The following review is part of Macworld’sSummer of Mac Gems series. Macos mojave torrent. Each business day until the middle of August 2008, the Macworld staff will use the Mac Gems blog to briefly cover a favorite free or low-cost program. Visit the Mac Gems homepage for a list of past Mac Gems.

Wish your Mac had another display so you could spread out your workspace? Most Macs support multiple displays, but for those that don’t—or if you don’t want to go out and buy another monitor—ScreenRecycler 1.16 lets you use another Mac as your second screen.

Connecting Mac Mini To Imac

Using VNC—the same technology as Leopard’s Screen Sharing feature—ScreenRecycler “connects” one Mac’s screen to another Mac over your local network. Macos mojave 10.14 iso download.

Screenrecycler Reviews

Screenrecycler Download

Performance isn’t as good as a direct display connection, but for text documents, palettes, and other non-demanding items, the virtual display works well.