I am trying to generate a reminder for our laboratory analyst to
perform a certain task with our samples at a particular time. The time
at which she needs to do this task (end time) will be in a particular
cell. This end time is based on the addition of 2 hours to another
cell that contains the start time.

So I would like to add the current time to a different cell and have it
be frequently updated using the computer's clock. This will give me
something to which I can compare the time described above. I need this
same event to occur over multiple worksheets but only happen on the one
being currently used.

Thanks so much for any help that anyone can provide!