Heard about this on the radio: Intellifit (warning: annoying Flash site) has adapted airport scanning technology to measure your body dimensions to suggest correct clothing sizes. Using your scanned dimensions and your fit preferences (baggy, slim, etc.), the machine gives a list of compatible clothing.

This would be great for online shopping. You could get scanned at a local mall and your size and preferences could be made available to several online vendors. I'll never have to shop offline again!