Automatic counter code (not page counter)

I am trying to create a counter display that will automatically update itself and count upwards. It is for an intranet where I want to simulate the number of customers we have served i.e. if on average we serve a customer every 2 seconds I want to be able to code this so that staff see the 'current' number we have served this year each time they log in.

For example...

"We have served 23,567 customer so far this year"

Has anyone got any ideas on how I can achieve this effect??
Any help apprieciated.
OD :confused:

I have just seen the 'countup script' post in this forum. This is sort of what i need but just counting numbers, not dates!

:D