Last night, due to Edgware Road (Bakerloo Line) closure, I had to travel from Paddington to Waterloo on the tube. The ticket gates at my most convenient entrance were broken, so I lost five minutes trying to locate someone to explain the situation to and get myself in without having my Pay-as-You-Go Oyster card penalised for fare evasion. This meant that, even though the tube was on time (well, two minutes late compared to what it would have been had I been able to board at Edgware Road as I used to), I missed the fast train from Waterloo to Hersham.
The train was then two minutes late, though the delay was accrued outside of Zones 1-6, so doesn't count. Still, that made for a 26-minute delay overall (£65).
This morning, the train was a minute early to make up for it, which would have allowed me to catch an earlier tube, had it not been two minutes late. Arrived at work one minute earlier than planned nonetheless, so that's £2.50 back to TfL for a grand total of £62.50 to Signal Failure.