Modding a Wii isn't as hard as you'd think. Modding a game system used to involve lots of fun opening up a game system, inserting chips or other various items, tinkering with the internals and dealing with the fact that going online or playing games with certain anti mod software was no longer available to a system modified in such a way.
And then there was the amount of risk for those not well versed in physically modding a system; hard modding could cause irreversible damage if done wrong, and the loss of money (and even your system) to untrustworthy people that offer the service.
But of the big three current gen systems, the Wii has made modding a viable option. Unlike past systems like the Xbox or PS2, modding a Wii doesn't require any physical tinkering and costs way less then one would think. In fact, modding a Wii doesn't take more than using an SD card, the same type of card that a digital camera uses.
Wiis have SD slots to expand the amount of space it can hold and to allow a user to post pictures from a digital camera to the Wii. But crafty hackers have found that more than simply photos can be sent to the Wii in this fashion: hack files.
Many have that hacked their Wiis are able to play back ups, DVDs, youtube videos and more on the system. The methods out there are great but I myself use the flash memory on my SD rather than an in case modding. You only need to purchase a few things to do this, things you may already have.
HDSD cards and an SD reader
A SD card is the same as the thin small chip that is used inside of a digital camera. Small and light, they come in as small as 2GB and much larger. The Wii has both a slot for an SD card in the front of the unit almost resembling a memory card slot. The SD card slot was intended for saving small things like on system pictures and uploading pictures from your camera.
But if you add in a SD Reader for you computer, and then that tiny SD card can become a small boot up disc of programs to download to the Wii. Downloading programs such as BootMii and NeoGamma on your PC, then transferring them onto an SD through the reader is almost the equivalent of making a floppy full of cracking software just for your Wii. The upside about using a card in this way as it doesn't have to be formatted for the Wii. So you could technically store Wii files and computer files onto them.
Getting the right model number/version
So you have an SD reader and some HDSD cards. You have a bunch of programs you want to test on your Wii. Before you jump for joy, look up that Wii's model number and update version. If it's not version 4.1 (or lower) or worse, has been fully updated with all current Wii updates, then most likely you will not be able to soft mod it. (Soft-modding is what we've been talking about, meaning we aren't modifying any hardware, just letting the software hack files do it all.)
Keep in mind the soft modding methods out there will void your warranty with Nintendo and that if you send in your Wii for repair, Nintendo can and will replace anything not up to date. This includes hardware and software patches.
Now why would Nintendo do this? Because every update is a hot fix or backdoor fix. They basically are being nice and saying, 'stop tinkering with our system'. So if your Wii has a major issue, try to find a technical friend first. Only send your unit in as a last resort.
Portable Hard Drives
Eventually that SD card will be full of hacks, back up games and the like. HDSD cards only hold but so much. This is where a portable Hard Drive can come in handy. A 100+ HD can store many back ups and files and can easily be loaded and removed.
The following was added by Jason Rybka, your Guide to Video Game Cheats here at About.com.
Finding More Info About Modding Your Wii
In this article we really only touched the surface of modding a Wii (or any console for that matter), there are much more detailed articles out there. Our Nintendo Guide Site has a slew of info on modding, a guide to homebrew, and many more of the advantages of having a modded system, I suggest looking there as your next step.
And from there, there are always going to be tons of in-depth articles on Google, Yahoo, or your favorite search engines. You just need to know some of the right terms to look for, which we've given a good start here. Expect to see more articles on this topic right here at the Video Game Cheats, just keep an eye on the blog. Enjoy your Wii.