Cheapest GSM  is $3/month  @ $18 for 90 days but it actually works for 6 months if you save minutes (120minutes +20 bonus minutes) Comes with a free reconditioned set, local rate to Mexico, Canada, Europe etc and also Bangladesh, NO Nepal. Free incoming text, outgoing 4 cents/SMS. This is a Tracfone deal with Motorola V170 at tracfone.com. Google for free shipping and other discount codes or get it for around $22).

Family plan: Sprint (CDMA) is the cheapest, but manage a couple of hours every month to call customer service and argue over extra charge in your bill.

Never used, but virgin mobile has some good schemes for individual users.