Visual Boy Advance GX is a Game Boy Advance / Game Boy Color / Game Boy emulator for the Wii based on VBA-M
From Network (using SMB)
Using the emulator via network requires that your Wii is configured for your wireless network, and that you’ve set up a file share. You must provide a username, password, share name, and IP address to log in to the file server (in settings.xml). This XML file is created for you upon first loading the emulator and entering/exiting Preferences. Here’s an example snippet for your XML configuration file.
Full details http://wiibrew.org/wiki/Visual_Boy_Advance_GX