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Turn your Wii into an AppleTV.
This application basically allows your Wii to operate like Front Row or an Apple TV. It's brain dead simple to use, and you have the option of streaming movies, or converting them to play from an SD card within Wii's Photo Channel. As long as you have a Mac with space for all of your movies to stream from, you can watch anything, as well as look at photo's from iPhoto, browse and play music and your playlists from iTunes, and even use your Safari and Firefox bookmarks to browse on the Internet Channel (which Wii Transfer requires). Converting movies is a simple drag and drop, nothing else to it.
Pros: Turn's your Wii into an AppleTV, without needing HD.
Easy to use interface.
Very inexpensive. People who complain about software costing money, this is $19, that's a few trips to Burger King, which I know you don't complain about. So get over yourselves.
Cons: Since the Wii isn't HD capable, neither is the videos from Wii Transfer, however, they look just fine if your movies are of good quality.
Can't play DRM'd movies and music purchased through iTunes.