In The Netherlands, Asian food brand "Go-Tan" is running an interesting experiment of Bluetooth marketing in an Albert Heijn supermarket located in Den Bosch.
As explained on Emerce (in Dutch) custumers shopping in the supermarket (and anyone walking within a 100m distance) who has an open Bluetooth connection, are reached by a contact request from the Go-Tan device. The messages delivered through Bluetooth aim at making people aware of the discounted Go-Tan products available in the stores.
The action will last until the end of the week, and it's still too early to look at the results. However, it's already interesting to note that according to the Emerce article, over 25 percent of Dutch mobile users leave their Bluetooth with an open connection, which means that potentially Bluetooth could prove as a very appealing channel to establish a direct and immediate communication with end-users. Of course, "handling with care" it's always a must...