You could always look into grabbing a router that has failover capabilities..... and tether your data connection to your cellular phone -- if one connection fails, it automatically switches to the back up connection.
I have something similar here. I have my cable connection, redundant #1 is the near by golf course's free WiFi ( they use DSL ), and redundant #2 is is a Virgin Mobile Cellular Hotspot.
I was thinking about this for a long time.
Not sure how to setup this tho.
I can setup my android phone to act like wifi router thats not a problem but I have no idea how to process further for setting up my dsl wifi router
btw I have asus DSL-N66U