DX just made Ceramic MR16 Light Bulb Sockets available for $1.28 with free shipping.:D
http://www.dealextreme.com/details.dx/sku.13920

http://www.dealextreme.com/productimages/sku_13920_3_small.jpg

If your wondering how you would use the above socket;
http://www.instructables.com/id/BIKE-LIGHT-500-Lumen-%22Mt.Bike%22-for-under-10-bucks-/