I just switch my account around a bit.
My previous arrangement was:
Line 1:
1400 minutes for $80
Unlimited international data for $65
Family unlimited messaging for $30
Line 2:
Additional line for $10
Unlimited data for $30 (About 100MB used a month)
Line 3:
Additonal line for $10
2GB data for $25 (About 200MB used a month)
Line 4:
Addtional line for $10
3GB data for $30 (About 500MB used a month)
Line 5:
Data only for 5GB on iPad for $50 (About 2GB used a month)
Total is $340 a month just for the basics. No tethering, throttling on the unlimited data.
Now I decided to switch the other lines that didn't use much data to the mobile share
10GB for $120
3x lines for $105
2 additional iPads (where it was just one before) for $20
For the these 4 older and 1 new lines, it's now $245
I'm retaining the international data, so I moved my family plan to an individual at $40 for voice, $20 for messaging, and $65 for data. That's $125.
Now the total is $370.
That's all before my discounts which half my plans where not eligible for. I've gained unlimited voice on the extra lines, pooled data for the people who don't use much data. I pay for my parents, so now they can tether, go FaceTime over 3G in iOS 6; my mom's iPad can now have 3G data.
With discounts it goes to about $10 more per month; not too bad.