Neither the Ultronomicon nor the The Ur-Quan Masters (UQM) projects currently accept donations.
You can indirectly support these projects by donating to the projects they depend on. As is the nature of Open Source software, a lot of these projects in turn depend on other projects. Supporting any of those indirectly supports UQM.
You can also contribute to the cause of Open Source in general by contributing to organisations such as the Electronic Frontier Foundation.