Check it at the above link. From their FAQ:

This is a simple help for you to identify any unknown files on your computer.
While we still do not cover ALL of them, we might have some of the most
requested ones here. You can enter a filename and see if this file is a dangerous trojan,
malware, or simply a standard Windows file.

The site is in BETA and if you try a file that isn't listed, adding it to the site is as easy as clicking a link. Seems pretty helpul.