File > Link > select blend file > select proper grouping or object (it will depend on the .blend file).
To animate the linked character, select its armature, and do CTRL + ALT + P to make a proxy. From then on, you can animate the character as if it were an integral part of your project's .blend file.
See official documentation:
http://wiki.blender.org/index.php/Doc:Manual/Data_System/Linked_Libraries
Pay attention to the 'linking' and 'proxy object' sections.
See also this tutorial:
"How To Setup A Character For Library Linking"
http://www.youtube.com/watch?v=Bs2Hmdk3Vr4
| Project | Summary | Status | Priority | Category | Last updated | Assigned to |
|---|---|---|---|---|---|---|
| Blender | Animation scene: linking to fully rigged character | active | normal | support request | 30 weeks 12 hours |