The Nintendo DS remake of the old Dreamcast favorite Bangai-O Spirits has one very notable feature that we haven't seen in years. Kotaku found out that instead of using Nintendo's local Wi-Fi or over-the-net DS codes, you share levels via audio recording. Once you've designed something you want your friends to see, it'll play back that level as an audio recording that you can record it as an audio file on your computer, then send however you send files normally.
To get the levels back on another DS, just play it back over your computer's speakers and hold up the DS mic to it-the mic will grab the sound and the game will change it back into level code. If only Nintendo didn't make their online system so horrible to use, the developers wouldn't have to resort to archaic methods that are pretty much on par with tin cans and strings. [Kotaku]