use mobile broadband to replace DSL line?

I see boost mobile unlimited web access is 35c a day. So If I use that every day, it will be 10.5$ a  month.   It is much cheaper than what I am paying for DSL (40$ without phone line). The DSL speed is 3 Meg.  CDMA evdo speed is similar to that, right? As long as I enable tethering to computer, a phone can be my broad band modem at home.

Is the idea crazy? How to connect router and cellphone?