That a piece of hardware is LinuxCompatible is to say that either it adheres to a common standard that has already had a driver written for it, or that a driver has been written for it already.
Things that are LinuxCompatible include (you can't go wrong with these):
Sound Blaster Live DEC Tulip Realtek 100mb network cards Microsoft USB mice/keyboards
Things that are not LinuxCompatible include:
Phil's card reader/camera?
One page links to LinuxCompatible:
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