Nintendo appears to be finally adding the option to purchase downloadable games with the rewards points earned within the Club Nintendo website.
A new front page on the US Club Nintendo site went live briefly (before going down for "maintenance") revealing new Virtual Console and 3D Classics offerings in exchange for Coins earned via Nintendo game purchases.
A (pictured) snapshot of the page before it went down (taken by a NeoGAF poser - thanks Shack) shows that, among the spoils available were Super Mario Kart on the Wii VC, and the 3D Classic version of Xevious for 3DS, both up for 100 coins.
At least this gives you something actually worthwhile to spend those smaller Coin amounts on rather than the rubbish desktop pictures you can download for free elsewhere.
Although this appears only to apply to the US arm of Club Nintendo, the EU version does already offer Nintendo Points cards - the currency used for Wii, DSi and 3DS' digital stores - in exchange for rewards points (Stars).