Maya

A simple to use skeleton builder and autorigger that builds a fast, animator friendly, bipedal rig. Some of the features include:

• Entirely node based.
• Fully scaleable.
• Stretchy IK/FK legs and arms.
• Combo IK/FK spine with up to 18 joints (and true IK as of version 1.9).
• Knee and elbow snap to pole vector control.
• Standard foot controls including footRoll, footBreak, toeRoll, toeTwist, ballTwist.
• Space switching on all major control curves (including a tool to copy control positions across space switches).
• Support for upleg, upArm, and foreArm split joints (up to two each).
• FK/IK head controls.
• FK/IK fingers.
• FK/IK and IK/FK matching on the legs and arms.
• Auto align on relevant FK controls.
• A tool to create a skeleton for your character.
• A tool for quick and easy control curve mirroring and modification (includes lots of prebuilt control curves).
• A tool for easy rig removal and update.
• A tool for easy creation of a scaleable, stretchy IK spline joint chain (complete with FK controllers) from a curve.

 

More info, and the latest version, can be found here..