If you are using ext2 Filesystem there is a way how you *probably* can
undelete files delted with rm from command line. Important: The
blocks of the deleted file shall not be overwritten.
Thre is a tool called
This is a PERL script which invokes some low level ext2 functions.
You will find more information in the HOWTO "Ext2fs-Undeletion"
Here also the copy of the document in Web:
For other FS (e.g. RaiserFS, XFS) I am not aware of any way to undelet files.