My new Wii

Your wii right now can play games, and let you pay for VC games. That's...pretty much it. If you hack it, you can install .wads which can be VC games that you would otherwise have to buy. If your wii wasn't black, you would have a different disc drive that can read DVDs for movies and becomes enabled with a certain application packaged with what you hack the wii with. The homebrew channel can be used for tons of things from brawl+ to emulators for GBA and playstation. You can get brick protection which means new discs won't auto update, you can skip the health warning screen and have it press A automatically, and you can make a backup of the entire wii's NAND.

I'm not going to freely post how to do all of these things though. Google it or send a PM.