How can I set a global shortcut in KDE (4.4) to run a bash script?
First make sure that your script is executable, e.g. like this
chmod +x ~/scripts/myscript.sh
Then create the shortcut using the tool which can be accessed by System Settings > Input Actions. Do a right click in the left pane where existing shortcuts are listed and say New Global Shortcut > Command/URL. Set the name to something sensible, choose your desired shortcut, set the command to your script, e.g. ~/scripts/myscript.sh and tick the Enabled box. If you put your script in a folder in path, (following common conventions one would use /usr/local/bin) you can skip the path in the command and just write myscript.sh.