One of my new tools in my layered security blanket is a site called virsustotal. What is great about this website is that you can take a link in an email, copy and paste it into the search field and then scan it without harming your computer. (Note: you have to click on the scan URL link below the scan button to switch from the default scan file mode.)
The other plus is you can download a file from a website, and have it scanned by not one many different antivirus vendors.
It should be noted that this website application does not “guarantee” that the program you download is not a virus, worm, trojan, or malware. In fact no antivirus program can provide 100% protection, but it does provide another layer of security.