Dell furious at his Twittish daughter -

Tinman Michael Dell is apparently furious with his teen daughter after she made a mockery of the $2.7 million he spent on security.

According to Bloomberg, Dell has shut down daughter Alexa's Twitter account after she revealed so much about his movements online, it was a doddle to plan an attack.

Alexa, 18, has been detailing her every move on Facebook and Twitter down to the exact arrival times in New York City to a list of her favorite shopping hot spots.

It is enough to give her minders a heart attack as it allows any would be kidnappers to come up with a decent plan.

The last straw was when Dell also posted her high school graduation dinner invitation that foretold where and when her father and mother would be within a couple of weeks.

Alexa's dad pays about $2.7 million a year for the security protection of his family, according to Dell's regulatory filings.

Kids posting on social networking sites are fast becoming a nightmare for security companies trying to look after rich CEOs. Besides kidnapping, the posting personal information on social media sites can lead to a variety of security breaches. A well informed hacker can use some of the data to guess passwords.