I was talking to VISAman the other day and he has come up with some interesting thoughts on the increasing chances of getting found out, the closer you get to your destination.
This is born out of hearing people on the train (generally contractors or an inexperienced Exec) talking loudly about this customer or that customer who is a complete arse.
Alternatively they might be talking about a severe system problem which really no-one else should hear about for business protection reasons.
The idea is that, when you are travelling to work, the closer you get to your office (or customer's office) the more likely it is there will be someone within earshot who will either know you or know your customer or indeed, be your customer.
Moral of the story, keep your trap shut on the train and don't make business calls because you are probably damaging your business.
Also, it's so very annoying and it doesn't make you look big and important to talk loudly on a phone on the train.