The best use for Smart Actions that I have is to do things such as:
1. Turn my phone to vibrate when I am at church based on the location and time triggers.
2. Turn my phone to vibrate when I am at a meeting at work based on the location trigger and my outlook calendar status.
3. Turn my phone to silent allow background syncing turn on Wifi when charging at night and the allow audible rings from my VIP list if it is family assuming that if they call me at night they have a good reason.
However since the Verizon version of ICS smart actions is quirky and will not always program correctly (will not save a new rule). I have to use a suggested action then edit it extensively. It worked like a charm under GB.