This is a simple Google Maps app tied back to UK railway station usage data, grabbed from the ORR.

At any given time, you should be seeing the 10 most used stations within the map view. Click on the marker for 07/8, 06/7, 05/6 and 04/5 data.

Note that the mechanism for generating the data has been changed/improved over the years which means that there can be some sudden jumps in figures.