I found this great link to help open email attachments:

Encryptomatic’s Free Online Email Viewer

It doesn’t happen often, but every once in a while, someone will send me an email attachment.  It is either a file that ends with “.eml” or a winmail.dat file.  GMail can’t open those attachments; it has a “View” link but that just shows the raw text that can be very hard to read.  Now, I can use this tool.

The tool says that you can “Upload and View a .EML, .MSG or winmail.dat message”.  I haven’t used it a lot, but it has worked for me so far.  The only problem that I have had is that I haven’t gotten winmail.dat files to work yet: