Another way to restrict the use of your E-mail message and protect your privacy is to set the message to expire.

另外一种限制使用你发送邮件来保护隐私的方法就是给邮件设定过期期限。

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The e-books will expire at the end of the 21-day lending period.

CNN: New Sony Reader adds touchscreen, wireless downloads

Re-establishing ISPs as safe-havens for terrorists: One provision of the Patriot Act (Sec. 220) due to expire shortly allowed federal judges to issue nation-wide search warrants so that investigators could examine unopened e-mails stored on an Internet Service Provider's computer server, even one located outside of the judge's district.

CENTERFORSECURITYPOLICY: 50 Patriot Act supporters warn against Act's lapse