SlackBuildsOrg/network/spice

Spice is an open remote computing solution, providing client access to
remote machine display and devices (e.g., keyboard, mouse, audio).
Spice achieves a user experience similar to an interaction with a
local machine, while trying to offload most of the intensive CPU and
GPU tasks to the client. Spice is suitable for both LAN and WAN usage,
without compromising on the user experience.

This requires spice-protocol and celt051.  libcacard is an optional
enabled by passing the switch CACARD=yes) dependency.