I was looking for a way to make my phone (N900) ring for certain contacts even if a Silent profile is selected. Some preliminary googling did not lead to anything, so I rolled my own. Here's what I came up with:

• install dbus-scripts
• create a file /etc/dbus-scripts.d/ring-important with the following contents:
  
  Code:

  /home/user/bin/ring-important * * com.nokia.csd.Call Coming

• create a file /home/user/bin/ring-important with the following contents:
  
  Code:

  #!/bin/sh
  INCOMING_NUMBER="$5"
  IMPORTANT_NUMBERS="/home/user/important-numbers"
  
  if fgrep -q $INCOMING_NUMBER $IMPORTANT_NUMBERS; then
      run-standalone.sh dbus-send --type=method_call --dest=com.nokia.profiled /com/nokia/profiled com.nokia.profiled.set_profile string:"general"
  fi

• set the script's executable bit:
  
  Code:

  chmod +x /home/user/bin/ring-important

• create a file /home/user/important-numbers with a list of phone numbers you'd like to ring even if the phone is set to Silent, one phone number to a line
• restart dbus-scripts:
  
  Code:

  killall dbus-scripts

This will set the profile to General whenever there's an incoming call from one of the numbers listed in /home/user/important-numbers. The profile stays at General after the call is finished.

Hope someone finds this useful.