I'm using Wifi, but it's an actual gateway, not a mobile hotspot. The crashes and speed problems are ethernet issues, also. I've looked into the interference issue-- I've moved the router over to a phone jack with a cat6 cable, so that should minimize radio wave interference. As for other electronics, it's not near any that are ever on, so that's pretty much open and closed.
My guess is that it's just a heavy draw on the infrastructure that isn't up to par around here. Since this is a college spillover town for a university that started today, it's probably just that all of the students came back and put a heavy load on the ISP all at once. It did just appear suddenly the day before move-in day, so it's possible that the ISP itself is throttling existing users in anticipation for the new patronage of the heavy net-using college students.
I've talked with the ISP numerous times about problems with speed and crashing service. They've pretty much tried everything they can think of, from installing cat6, to eliminating 50 foot lengths of extra cable by the street. They also fixed an issue where we were on the same internet/phone line as the neighbor, which caused a great decrease in speed and large increase in interference, however that problem has not been completely solved yet. I'd be harsher with the company, but I think they are well aware of the fact that they are the only option in town, so there is little result when you threaten to leave if rates aren't lowered or speed heightened. And most days, when you decide to call them, it's like they give your stats a boost while you are talking to them so that you no longer have a point.
TL;DR Lesson: Steer clear of AT&T if at all possible, especially if you live in the deep south.
Edit 1: This is what it's supposed to look like:
![Image](http://www.speedtest.net/result/2913372762.png)