This morning I received a curious example of data mining performed by Transport for London - an email warning that part of the station I use every day will be closed for renovation.
I highly doubt that they sent out this email to all the Londoners who use other stations - how many of them would care about a staircase at Finsbury Park? The only way for them to target me with this information is to data mine my Oyster travels and see which stations I use the most. While it is quite and obvious and expected that they will use the data in such a way, it still a bit scary. Even more so knowing that my Oyster card is registered with my real name and address.
There is nothing like starting your day with a small reminder that someone out there knows a lot more about you that you think.