Try this:
http://www.mysql.com/doc/en/Date_and_time_functions.html
SELECT DATE_FORMAT(NOW()-010000,'%T')
This will give you the time minus 1 hour.
Basically when NOW() is used in a calculation it will reduce the result into this yyyymmddhhmmss format instead of yyyy:mm:dd:hh:mm:ss.
So I took a wild guess and used 000000010000 by mistake(using my logic I should have used 9 leading zero) and it returned the correct answer. Stupid me, leading zero are useless in calculation😛, but for the purpose of clarity I used "010000" as if it was "01:00:00". '%T' returns the time from a the above yyyy:mm:dd:hh:mm:ss or yyyymmddhhmmss structure.