When the bag is checked in, the tag is applied, and the airline's computer systems associate the tag's code with the passenger's electronic ticket.

ECONOMIST: REPORTS

Moreover, big-box stores find themselves increasingly hard pressed to compete with online retailers ever since consumers became comfortable with buying big-ticket electronic products via the Internet (think Amazon).

FORBES: Whoever Ends Up Running Best Buy Could Inherit Happy Shoppers

Many consumers, in the market for big-ticket electronic items, shop Best Buy stores and then use the information and advice received to make informed on-line purchases at lower prices from retailers with less overhead than Best Buy.

FORBES: Best Buy In Turmoil: Will It Survive?

While this practice, akin to ticket-scalping, can be quite profitable (especially when purchasing must-have electronic gifts) and is not illegal, it does require some dedication and standing in long lines.

FORBES: How To Be $1,000 Richer By 2012

Electronic tickets were less common back then, and the festival organizer had written to tell me that my ticket would be waiting at the KLM counter at the airport.

WSJ: Etgar Keret on a Bumpy, Post-Sept. 11 Plane Ride | Traveler's Tale

Despite being called "e" (presumably for "electronic") vouchers, they are not redeemable online at Amtrak.com or at the railroad's QuikTrak ticket kiosks.

ECONOMIST: Business travel