http://abclocal.go.com/wjrt/story?section=news/bizarre&i...
$22,000 bill because son's data use wasn't covered in family cell phone plan.
http://www.switched.com/2007/12/14/man-gets-slapped-with-85-...
$85,000 phone bill. "It turns out that he was being charged on a per-kilobyte basis because his unlimited browsing plan didn't cover using the phone as a modem. As a "goodwill" gesture, Bell Mobility has dropped the bill to measly $3,243."
Finally, here's one from Telstra:
http://www.blackberryforums.com.au/forums/general-bis-discus...
"I have recently signed my BB 8800 up on a Telstra $39.95/mth plan which I understood was for unlimited email and internet browsing. I got the shock of my life when I checked my data usage online and saw a bill for $250+ after only a couple of days. On examining further I note that I have not been charged for blackberry.net connections but heavily charged for wap.telstra."