More and more frequently, digital billboards are replacing the vinyl versions that have graced highways and bi-ways for generations. Such digital signage is allowing advertisers, including some for whom outdoor advertising is something new, to put time-sensitive and freshly relevant messages in front of drivers' eyes. The technology also allows for multiple advertisers to buy time on the same sign during different day-parts. Right now there aren't many of them but those that are in action are seeing significant return on what is, admittedly, a hefty up-front investment.

Personally I've only seen one of these in the Chicago area but thought it was interesting enough that I paid it a bit more attention than I would have a traditional billboard. But I wonder if that's just the novelty factor and if these won't fade into the clutter eventually as well. Plus, I'm not so sure that attracting the eyeballs of someone cruising at 65 miles an hour to a flashing and moving sign is the best of ideas. I'm just saying.