Impressive Wii emulator Dolphin has recently been updated to include the ability to access the Wii Shop Channel, from which users can actually buy and download games.
Emulation can do amazing things for the SD Wii game visuals, presenting the likes of Skyward Sword and Super Mario Galaxy is crisp HD, but is often criticised for its reliance on pirated/illegal software.
With access to the Wii Shop, users of Dolphin can actually give back to Nintendo by paying for the games.
The complexities of Dolphin mean it's not super straightforward to get up and running, but there are plenty of useful guides online which should help out those wanting to give it a try.
There's also no telling if Nintendo will close down access to the Wii Shop, and if so what would happen to your purchases.