Two weekends ago I participated in the Global Game Jam along with some fellow students at the MDM program. We all spent 48 hours working with other game design enthusiasts around the world making games. You can check out the games at globalgamejam.org The team I forged with created a game called “Slast” using the Unity Engine. For most of us on the team that meant we were learning an engine and creating a game at the same time. I used the time to do some scripting for the spikes as well as getting a chance to step out of the programmer role and try some 3D Modelling and art. It was quite fun and I liked designing it alongside the modeller who did the Giant Spider. Keep in mind the name of our group when you play it as none of us were real artists on the team, but we still came up with something decent.
As far as Unity goes, I would definitely use it again sometime. It is quite handy and has lots of features. I’ve used the Blender open source game engine and would say that Unity is better than Blender since the interface is unified (a lot of the shortcut keys are similar to Maya) and it exports so well to many interfaces.