A biometric time clock would make my life a whole lot easier. I have all of my employees punch a time clock, and on numerous occasions, I have checked the time cards during the day and found that an employee or a few employees were punched in on the card when they were actually on lunch break or off doing something not related to the work they are paid to do.
Some time-card mistakes are innocent enough, and there are times when punching the clock for someone else or having someone punch your time card would really make sense because of the convenience. The only problem is that once you allow this to happen once, the practice grows until you have people away from work for a couple of hours and still on the clock being paid.
My policy is simple. If you are caught punching someone else's card then you can expect to be fired on the spot. This will remain my policy until I can afford to buy a biometric clock.