I have 2-3 monitors I'd like in this setup. My Dell monitor can do what you describe, but lacks the ports of a real dock (don't think it has outgoing Ethernet).
At the moment I have 2 monitors on the dock (which is my main setup) and a 3rd monitor on a separate machine with KVM (which means 2 keyboards and 2 mice) - this supports 4 computers (2 laptops, 2 desktops) - work+home laptops on the dual-monitor dock and Linux+PC desktops on the KVM. It's not a pretty setup.
At the moment I have 2 monitors on the dock (which is my main setup) and a 3rd monitor on a separate machine with KVM (which means 2 keyboards and 2 mice) - this supports 4 computers (2 laptops, 2 desktops) - work+home laptops on the dual-monitor dock and Linux+PC desktops on the KVM. It's not a pretty setup.