BNetCommander is a tool for editing battle.net gateways, letting you re-order, edit, or add new gateways to the list. It can edit gateways for StarCraft, Diablo 2, and WarCraft 3.
I'm no longer able to support it so I put the latest source up on here in case others might want to support it. There's some source floating around but I think it's old.
Just a warning, this is one of the first applications I wrote so the code is pretty awful. I may or may not find time to clean it up a little.