Eraser does a very good job at destroying data beyond recovery. Its extensive erasing capabilities make sure that not even a trace remains after erasing a file or folder.
This newest release has an "Erase for Good" feature that can destroy any data from previously deleted files that may still be accessible on your disk. A new "Sensitive Data Cleaner" clears the contents of folders that usually contain sensitive data, including your Web browser cache (or Temporary Internet files folder), cookies, history, the recent document list, and more.