In some interesting research by Siemens, wireless data has been successfully, wirelessly transmitted at 500Mbps using white LEDs.
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(The former record was 200Mbps.)
While light data transmission sounds less convenient than RF, there are many instances, like hospitals, when you don't want extra radio frequencies floating around. As for the system's range, apparently five LEDs can combine to beam data over "long distances," though we're not really sure what that actually means.
Still, it's interesting to see more and more uses come from LEDs. [Siemens via Engadget]