Check out this site:
http://www.wireless.att.com/learn/why/3gmicrocell/
Help for AT&T iphone users is on the way. AT&T is rolling out 3G micro cells. These work like routers, giving you 3G access that includes sending and receiving cellphone calls over the internet. Cost is $150 one time charge.
It doesn't solve issues driving around the Lake, but will solve problems in the home.