The xtreme0800.bin was only used with earlier versions of the xtreme firmware. It was purely to get your drive detected by Windows.
It's no longer needed with the newer versions of the xtreme firmware because you now use the enable0800.iso that's included in the newer firmware releases to get your drive detected in Windows.
This means that you don't have to re-flash your drive with xtreme0800.bin each time you want your drive to be detected by Windows. You just connect your 360 drive to your PC and place the enable0800 disc in your 360, wait about 10 secs and then remove it and boot Windows up and your drive will be detected.
Just make sure that you burn the enable0800.iso onto a high quality (Verbatim, Mitsubishi) DVD+R DL disc with CloneCD (The readme in the newer xtreme firmware versions don't tell you this, but trust me, many people have tried other ways). It has to be burnt this way or it may not work (this is very important).
I hope this helps clear it up for you