Windows only: It's no secret that the default copy handler in Windows is miserably inadequate. KillCopy runs circles around the default handler with tons of customisable options including a secure over write of moved files.
Killcopy, like well-known rivals, TeraCopy and FastCopy, handles local and network file transfer with radically more efficiency than the default Windows file copier. There are a host of features including the ability to toggle settings like copy verification for important files, parallel read/write to boost speed, and whether to prompt, overwrite or skip if a file already exists. The feature that really sets KillCopy apart from other custom copy handlers is its ability to securely overwrite file locations. You can instruct KillCopy to scrub the previous location of a file with 1-3 passes of data, making secure deletion part of your basic file handling. KillCopy is freeware, Windows only.