I usually don't go for the kitchy apps, but I have to admit, I have this playing right now. Instant Elevator Music
is an application that will play some light elevator music while you wait for files to copy or load. There's something I like about that. Whether it passes JeffSand's 7 Day Rule
It works with Windows Explorer while copying or moving files, IE and Firefox for downloads, Microsoft Office and Visual Studio, and several other applications. It runs in the Systray and is easy to turn off with a double click. Settings allow you to choose your own MP3 in case you have a different idea of what elevator music should sound like. It runs on XP and Windows 7, uses .NET Framework and I can confirm it works on 64-bit Win7.
Image: Gregory Szarkiewicz