Here is a list of threads with info on various extras, modifications and so on created by the community!
Key to joystick mapper
Lets you use a gamepad/joystick to play penumbra.
http://frictionalgames.com/forum/showthread.php?tid=778
Enabling free saving
Lets you save the game anywhere you want.
http://frictionalgames.com/forum/showthread.php?tid=862
Read the notes
A small application that lets you browse and read all the notes in Penumbra.
http://frictionalgames.com/forum/showthread.php?tid=864
Easier combat, simplified swing
Info on how to enable the easier combat mode that does not require mouse swings.
http://frictionalgames.com/forum/showthread.php?tid=860
None localized voices Boxed version only!
Play with the text localized but keeping voices in English(instead of German/Russian).
http://frictionalgames.com/forum/showthread.php?tid=916
Better Motion Blur
Shader that makes motion blur much faster (Warning: only for Shader Model 3.0 cards)
http://www.frictionalgames.com/forum/sho...hp?tid=726
Nvidia+Vista+Lag Fix
http://www.frictionalgames.com/forum/sho...4&#pid7544
WiiMote Script
http://www.frictionalgames.com/forum/sho...p?tid=1007