aka Double Your Bits For Free!

That's right - if you bought a Win32 version of XP and you're ready to move to x64 on your AMD64 or Intel EM64T-based system, Microsoft are running an exchange program that lets you swap over.

It's still early days for the new OS, so it's advisable to do some research on the drivers you'll immediately be able to find versus what you're currently using the computer for (the Upgrade page goes into more detail).

Note: Orders for the Technology Advancement Program must be placed by July 31, 2005.