It happens to be that Eraser has another nice feature which is pretty unique if you ask me. You can access the program Eraser Verify from the start menu or by starting verify.exe in the Eraser directory. This little program lets you erase single files with different algorithms to make it impossible to recover by normal means. Every step is shown in a hex editor which means that you can verify on the fly that the file becomes unreadable.

The process itself requires minimum user input. Select the algorithm or keep the default one, select the file that you want to securely erase and click on Erase. The file will be shown before Eraser begins the process to show you how it originally looks like. If you click continue in that step Eraser will start its work. You see how the file looks after every step which means you can verify that the file information have been deleted.