Non-Profit Challenges You to Ditch the iPhone for a Day

A non-profit organization called Reboot has a mighty challenge for you this Friday night: Power down your cellphone, let your FarmVille crops languish and sign out of Skype for a full 24 hours.

Conan Launches a Twitter Contest for Tour Tickets

If you weren’t able to pick up tickets for Conan O’Brien’s “Legally Prohibited From Being Funny on Television Tour” the first time around, you’ve just been given a second chance by way of a contest the former late night host announced on Twitter.

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Apple Now Accepting iPad Apps

Calling all iPad and would-be iPad developers: Starting today, Apple will be accepting apps for review.

“Predators” Trailer Hits the Web [VIDEO]

The Predator franchise of science fiction/horror/action films is coming back into the zeitgeist, this time without the Aliens.

Apple vs. Amazon: The E-Book War Rages On

The e-book war between Amazon.com and Apple is

getting uglier. Dennis Johnson cites a report in Publishers Marketplace (subscription required) that alleges that Amazon.

The Small Business Guide to Google Apps

This post originally appeared on the American Express OPEN Forum, where Mashable regularly contributes articles about leveraging social media and technology in small business.

Now in Production: The First Google Android Car

The first car equipped with Google’s Android mobile operating system will hit the streets this April 23.

Twitter Search Results to Show Popular Tweets On Top

Twitter appears set to tweak search results to return the most popular tweets first — instead of the most recent — for any given search query.

Analyst: Palm Shares Headed to $0

Following a disappointing earnings report, a Wall Street analyst has cut his price target on Palm to $0.