Nintendo concedes it can't smash homebrew R4 mod
It's not a reference to the eagerly awaited Wii title Super Smash Brothers Brawl. "We cannot smash them all." is a quote from a Nintendo spokesperson regarding unauthorized third-party modification devices for the DS.
The R4 is a microSD reader that fits into the Nintendo DS' Slot-1 port and bypasses all of the handheld's security functions, allowing a host of uses: playing music and movies, reading text files, creating homebrew software, and playing "backed up" - or copied - games.
The product requires no drivers, and copied games are fully supported, complete with Wi-Fi and the Rumble Pak - a plug-in device that makes the game physically shake at the appropriate moments. The R4 and the M3 DS -- a similar product reported to be produced in the same factory -- both retail for around $45 USD.
Products like these are technically legal, but the most common uses are typically piratical, and not looked upon favorably by Nintendo. Even those activities that fall within the legal uses of the product -- such as creating and trading homebrew games -- could be potential negatives for the system.
One can be sure Nintendo never intended support for games like (and I'm not making this up) "Porn All Stars" and "Strip Rock-Paper-Scissors."