If you're still chuckling over Steve Jobs' manila-envelope trick during the Macworld 2008 keynote, this one's for you.
The white Italian leather of the Inter-departmental Mail Computer Sleeve from Kena Kai is embossed with the address blocks found on a typical interoffice envelope. For thorough verisimilitude, the sleeve also incorporates a button-and-string closure.
The larger size ($79) accommodates ultrathin 13-inch laptops, such as the Apple MacBook Air and the Lenovo ThinkPad X301, as expected. But Kena Kai also sells a smaller version ($69) that's designed for Netbooks, such as the Asus Eee PC 901 and the HP Mini 1000.