Dollar sign on danish keyboard
It seems the layout may have been modified. 

Try using AltGr+Shift+3.

You can also check what key combinations produce what characters by enabling the On-Screen-Keyboard :


  
  Open System Preferences and go to “Keyboard”, and look under the “Keyboard” tab
  Check the box next to “Show Keyboard &amp; Character Viewers in menu bar”
  Enable the virtual keyboard input in Mac OS X
  Pull down the newly visible Keyboard menu and choose “Show Keyboard Viewer”