Is there anything working on Windows XP Pro x64? I think not. Point in case: I just tried to install the Intelli* software for my Microsoft Laser Desktop 6000:

Now come on. This is Intelli* v5.4, a version that is newer than anything to be found on MS' download servers (where you won't find x64 versions either).

Windows XP x64 at this point in time is only for people who are willing to put up with below-par driver and application support. This experience almost comes close to Vista Beta 1...

Update Turns out I was one day too early. The new version 5.5 can be downloaded now, and it supports 64 Bit (IntelliPoint 5.5 x64, IntelliType 5.5 x64 [one download for x86 and x64]).