I think it's a good idea to highlight VirusTotal's Email Submission feature, as I recently had to point this out to a couple of people.

In stead of using the VirusTotal's web interface or API, one can also send an email to scan@virustotal.com with the file to be scanned in attach (don't exceed 32MB) and subject SCAN (requesting plaintext report) or SCAN+XML (requesting XML report).

I usually get a reply after a couple of minutes. If I don't get a reply, it usually means that my attachment was detected and blocked by the email server I'm using, and that it never reached VirusTotal.

Didier Stevens
Senior handler
Microsoft MVP
blog.DidierStevens.com DidierStevensLabs.com