My university has implemented a java web-based version of Citrix Metaframe which allows applications to run off a server through a web browser. There is also a Citrix desktop client for OS X which can run Citrix .ica documents and link to the server apps without java or a browser. It's really a variation on "Remote Desktop" on an app by app basis. What is striking is that when you set your Citrix preferences for "seamless" windows, the Windows apps (Explorer, Word, Outlook, etc) all appear as individual windows within the Mac environment. They move around like regular windows, even behave correctly with Expose. With a broadband connection doing common tasks, these applications are virtually indistinguishable from local apps. Below is a screenshot (really this is for real, not a Photoshop) I have to believe that BootCamp is the first step towards this kind of integration with OS X. If a developer like Citrix can write a java application that can run Windows apps in Windows windows over a network in the Mac environment, I'm sure Apple could do the same with a local partition and Windows install. They've stated that a version of this is coming with Leopard. I'm guessing when you install Leopard you will be given the option of creating a Windows partition, and like now you can dual boot. But when in the Mac OS there will be a control panel to turn on Windows, and it's partition will rev up Windows invisibly, and the apps will simply appear in (fugly) Windows windows.