I have a tinypilot kvm. It's a nice network kvm that's pretty easy to get going. For example, it does 1920x1080 resolution immediately. I would use it more often, but it is loud - louder than the servers I hook it to.
I switched to pikvm which has a little less polish, but you can put together much cheaper. It is even more hackable. For example, connect to 4-port kvms that have RS232 and you can run 4 systems.
tinypilot seems to have some serial or order number that you need to download an update. pikvm seems to reserve some features for hardware they sell (for example, they don't seem to want to support HD resolution, even though you can just move an edid file and support 1080p at less than 60hz).
Both of them are or at least started as raspberry pi kvms with an HDMI-in digitizer (either csi or usb) and hardware hacks to use the usb power port to emulate usb devices (keyboard/mouse/drive)
I switched to pikvm which has a little less polish, but you can put together much cheaper. It is even more hackable. For example, connect to 4-port kvms that have RS232 and you can run 4 systems.
tinypilot seems to have some serial or order number that you need to download an update. pikvm seems to reserve some features for hardware they sell (for example, they don't seem to want to support HD resolution, even though you can just move an edid file and support 1080p at less than 60hz).
Both of them are or at least started as raspberry pi kvms with an HDMI-in digitizer (either csi or usb) and hardware hacks to use the usb power port to emulate usb devices (keyboard/mouse/drive)