The (US) Nintendo Online Store shows a rather sudden and surprising statement coming from Nintendo, claiming that the Wi-Fi USB Connector used to connect the Wii and DS to the Internet (wirelessly) has been discontinued "until further notice." Only those not owning a wireless router should be affected by the discontinuation of this product, while Nintendo themselves give Wii and DS users alternatives:

"The Nintendo Wi-Fi USB Connector has been discontinued until further notice," reads the statement up on the (US) Nintendo Online Store. "NOTE: The Nintendo Wi-Fi USB Connector is NOT required to connect your Nintendo DS or Wii console to the internet using your high-speed internet connection. If you own a wireless router, you should be able to go online without any additional accessories. Nintendo DS owners, click here for more information on connection options. Wii console owners can use the Wii LAN Adapter."

Nintendo hasn't mentioned anything about why they decided to discontinue the product for now, or whether it will come back to the market at all.

According to Wikipedia, ever since the DS was released on November 21, 2004, several groups have been attempting to extend and build upon the Nintendo DS Wi-Fi protocol. Two groups had claimed to be successful in tunneling the Nintendo DS Wi-Fi protocol over the Internet creating online multiplayer possibilities around the world by using the handheld's multiplayer-enabled games.

However, one of the groups never put out any software or evidence to support their claim. They have since completely disappeared, while developers moved on to create Dsmeet, a place to meet other NDS WiFi users. The other group claimed to have a workable system, but later publicly announced they were no longer working on tunneling the Nintendo DS, saying they were not making enough progress to warrant their continued efforts. In both cases, there was never any tangible product created.

So most likely, Nintendo's reasons of discontinuing the Wi-Fi USB Connector have nothing to do with people trying to extend its usage, not then and definitely not now.