Matthew Muldoon is the founder of Blendswap.com - a site where users can up- and download Blendfiles under Creative Commons licenses. The spectrum ranges from completely rigged characters to simulations and material libraries.
Miika Hämäläinen aka MiikaH is the inventor and main developer of both Dynamic Paint in Blender and he also created most of the recent improvements to the smoke simulator. BlenderDiplom talked with him about his efforts on Dynamic Paint.
Francesco Siddi is 3D artist and animator in the team for the upcoming open movie Tears of Steel. He is also in charge for the project's website. BlenderDiplom talked with him about the workflow they used and the openness of the project in general.