This is an Upgrade of the abandoned script created by Topazz (thank you) who left it to work only in KDE 3.x. I took it and adapted it to work properly on KDE 4.x. It now works in english, spanish and french. More translations are welcome.

Features:

Rename all files and directories, including sub directories, removing or replacing special characters.
The new name is compatible with MS-DOS FAT16 and URL (RFC 173
All characters different from A–Z, 0–9 and $-_!'() are renamed

For exemple :
* Fichier d'écriture *.txt
Will be renamed in :
-_Fichier_d_ecriture_-.txt

You can edit rm_special_char.py to change the new characters.

Installation:

You have to put the .desktop file to: ~/.kde4/share/kde4/services/ServiceMenus

You have to put the .py file to:
~/bin (local bin folder)
or specify the correct location in the path of the .desktop file.

If you have some path problems (like me) you can try to change ~/ to /home/yourname/