ANSWER
$666.66
According to Steve Wozniak, co-founder of Apple...
"I've always collected good phone numbers with repeating digits. It goes back to when I ran the first dial-a-joke in the SF Bay Area and needed good numbers. For example, I once had 255-6666 for dial-a-joke. We first knew that the Byte Shop of Palo Alto would be buying the Apple I computers from us for $500 each. Steve came up with something like $650 or $666 or, quite likely, $667, which is a logical 4:3 ratio. I spotted this and added .66 to keep all the digits the same. I'd never attended church nor read the bible so I didn't know of any negative connotation with 666. Neither did Steve Jobs. We were quite surprised when people told us. Sorry, but no connection."
- from Wozniak's website http://woz.org/
