Just received this US$100 phone from China (ZOHO V90+). It resembles the more expensive CECT phones but actually has more features. Dual-SIM, both active at the same time (including Bluetooth), quad-band GSM. Have a look at the reviews as they are quite positive.
http://www.dealextreme.com/details.dx/sku.13014
http://www.dealextreme.com/details.dx/sku.13541
I've been buying flashlights and small electronics from DealExtreme for over a year, and they've been quite reliable.