Just a quick heads up. GarageGames is currently raising money to port their recently open sourced Torque3D engine to Linux, including editing tools. Here’s a link to their IndieGogo page. They’re using a fixed funding campaign, so you don’t have to worry about losing your money if they don’t reach their goal.
We could use a capable 3D engine with mature, commercial quality editing tools on Linux (yes, there are other FOSS engines that run on Linux, but what we don’t have is something that comes close to Unity at the moment in terms of ease of use) — not to mention the fact that this would open the door for people to port a lot of existing games.
If you’d like to see this happen, stop by their IndieGogo page and help them out.