A friend of mine was planning on leaving work and wanted to do the same thing.
I advised her that on a properly set up IT framework, their IT staff would know
she deleted files. Unfortunately, once a file is deleted, there is little evidence
to show, that you had the right to delete it. FWIW, since it resides on their
computer... you really can't call it a personal doc anymore.
I told her, open the files you want to delete in a text editor and fill the file with
zeros instead.
As any true geek knows... this is still 'deleting', but with much less of what would
appear to be malice or intent. Plus, modifying a file might not trigger the same
flags that a delete would.
Of course, all the above is moot, if the company employs SVN, Git or any other
versioning methods.
-AI