This is totally legit, works with 1.4.7, and it'll probably work with 1.5 when that comes out. If you've ever tried to place water in the nether, you know that it hisses and burns up instantly. Rather than going the ole' bucket full of water approach, you need to go into creative and use commands. Once in creative, you can use the command: /give [whatever your name is, parenthesis not included] 9. This will give you a square that looks like water. If you right click, you can place it in the over world or the nether, but it'll stay in place. To get the water to flow, break the block underneath it and replace it. It might flow straight down if you have nothing underneath, but I'm not sure. Thanks for reading, comments and feedback greatly appreciated!