Unfortunately at my house I can't get 4G yet even though they have expanded and my phone is cable of it but tethering even the 3G connect has saved me from blinding off a bunch of tournaments when my cable internet died.
Three years ago around this time mid June to July my internet went out several times a week. The cable company kept sending technicians out to the main box on the pole to replace stuff before finally fixing the problem 3-4 weeks later.
It was super frustrating but tethering even 3G is enough as a backup for poker which don't use much bandwidth so it saved me several hundreds of dollars.
For more intense stuff like streaming you can maybe do light amounts of it over 3G but your certainly going going to be able to play a couple minute 720p video on youtube.