I've been sustaining myself for a couple of years now on my open source project (BookStack). Still going in a positive direction.
Other than that, some that come to mind: Proxmox, Opnsense, SnipeIT, GitLab, Canonical, Codeweavers/wine, Plausible, Home-assistant/open-home-foundation/NabuCasa, FreeBSD Foundation, Laravel, Blender, Godot.
Within there is a whole mix of business plans, some offer hardware, some are open core, some offer related paid services, some offer hosting, some offer support etc...
