Low Powered SOHO Server?

meroo asks: "I am building a new home that is completely solar/wind powered. I need to conserve power wherever I can, but I don't want to leave all my tech toys behind. I need advice about building a low power, Linux based, file and print server. It should be scalable to more than a terabyte of storage (we are video artists) with at least four HDD bays for flexibility and data redundancy. I would like advice on processor/mainboard combos, low power HDDs and a distro with the best power management to bring this thing down to idle when we are not using it. The server will be accessed via our laptops (Mac OSX and Ubuntu), a future home theatre PC and visitors assorted laptops. I've been looking at using laptop components, miniITX and professional server solutions, but now I'm thoroughly confused. Has anyone on Slashdot been faced with this problem before?"