Ever since i picked up a Nokia N800 back in the day, my go to setup has been a featurephone with bluetooth and a "smart device". Thus if i need a net connection right damn now, i can pair the smart device with the featurephone and get online.
Basically pair featurephone with smartphone or tablet, and then tell the smartphone or tablet to use the featurephone as their internet connection.
Mind you this is all on Android, and i am not American so i do not have to deal with carriers mucking up my featurephone firmware.
Edit: Just reminded myself that the term used is tethering. If i can't find a wifi hotspot to use, i tether smart device to the featurephone over bluetooth and thus use the phones mobile connection as the net connection for the smart device.