<p>Anybody know of a way to copy a file from path A to path B and suppressing the Windows file system cache?<br>
Typical use is copying a large file from a USB drive, or server to your local machine. Windows seems to swap everything out if the file is really big, e.g. 2GiB.
Prefer example in C#, but I'm guessing this would be a Win32 call of some sort if possible.</p>

I am not sure if this helps, but take a look at
Increased Performance Using FILE_FLAG_SEQUENTIAL_SCAN
.
SUMMARY
There is a flag for CreateFile()
  called FILE_FLAG_SEQUENTIAL_SCAN which
  will direct the Cache Manager to
  access the file sequentially.
Anyone reading potentially large files
  with sequential access can specify
  this flag for increased performance.
  This flag is useful if you are reading
  files that are "mostly" sequential,
  but you occasionally skip over small
  ranges of bytes.