Generating Random Phone Numbers

Often when you are writing code or testing an application, it might be helpful to have random phone numbers generated for you.
Here is an excel formula that I use: =value(left(substitute(rand(),"0.",""),10))
try these 2 instead (thanks to John)
=RAND()*(9999999999-1000000000)+1000000000
=RANDBETWEEN(1000000000,9999999999) [needs analysis toolpack add-in or excel 2007]
Even though it works most of the time as excel rand() formula generates long decimal values between 0 and 1, it often returns fewer than 10 digits. You can add zeros at the left side to compensate that though.
Here is a shared Google docs spreadsheet with 200 random phone numbers generated for you. I am not sure how often Google refreshes the formulas on shared workbooks, so please be patient if you see same numbers generated twice.