Recuva is a freeware undelete file and disk recovery application for windows.
It helps you undelete files on your computer, USB drive, camera or iPod. Recuva can recover files from a formatted disk that looks completely blank, find deleted emails, iPod music, restore unsaved Word documents etc. It fully supports Microsoft Outlook Express, Mozilla Thunderbird, or Windows Live Mail for your emails and Microsoft Word for unsaved Word documents.
It offers a Quick-Start Wizard for those who don't have time to play with recuva's options and deep scan capability in order to look for more deeply-buried results. Also it can securely delete files you want to erase forever.
Finally Recuva has support for every modern version of Windows and 37+ languages.
Portable download link: Recuva portable