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If you use POP E-mail, just open the item in the "Message source" view, available in one way or another in nearly all POP E-mail programs. The item is then opened in Notepad, which displays text only and cannot execute any embedded malware. You can also read the full header, this way.

If you use Webmail, check with your service provider to see if they filter such stuff or provide a "view source" mode.

This is old, but sound advice, stuff every techie ought to know.