Is terrible. I swear I have some of the worst internet ever.
I use a broadband wireless Sprint card, and our internet has been getting bad for a while now, but now it's just horrible.
My mom called Sprint to figure out what the hell was going on, and apparently "Typical users have at least 5 cell towers in their proximity."
We have 2. Out of those 2, one of them is down, and has been down for a long time.

They should fix that.

Aes_Sedia5 has it right on. I'm a bit worried that at any given point there are at least five cell towers in my proximity (for my carrier or not). I guess the specifics of the term "proximity" are not known (10miles? 1 mile?).

There's really not much you can for converting a 3G signal into WiFi. You could look into WiMax, and see if there are any towers or carriers around. I believe Sprint supports WiMAX is the form of 4G. See if you can purchase a 4G to WiFi device from Sprint, but first inquire if that'd help your internet connection. Those devices aren't meant to run a household, either. It's best to keep one to two devices connected to them at any given point, but that won't help you gett internet sadly