Foldit is a Rosetta-based game which effectively crowd-sources the protein folding problem. Foldit relies on human intuition and problem solving to find low energy protein conformations, instead of the typical Rosetta approach (Monte Carlo exploration of conformational space). Foldit has been successful in protein structure prediction and protein design problems.
Foldit is meant as an easily accessible general-purpose interface for Rosetta. Not all Rosetta protocols are integrated into Foldit, but it does provide push-button access to core Rosetta algorithms like the energy minimizer and sidechain packer. If you have a research problem that could benefit from crowd-sourced protein modeling, email the Foldit team!
A non-game version of Foldit is also available for individual use. Foldit Standalone is intended for scientists in a research setting. The user may load and modify custom PDB files using Rosetta via the Foldit GUI. Foldit Standalone does not communicate with Foldit servers or have access to crowd-sourced Foldit challenges.
For more information see the Foldit homepage. The original publication describing Foldit can be found here (PubMed link).