I went to a one day conference in London and, to save costs, decided to take the coach overnight (depart Leeds at 1am and then leaving London at 9pm in the evening - sleeping on the coach both ways).
The train worked out at £40ish each way (I didn't know I was going till a couple of weeks in advance, if it had been months I'm sure I could have bought tickets for less).
Using Megabus, I paid £4 to get there, £8 to get back ... and then had to pay £9 to get a taxi from the city centre to my house.
The train does have a huge speed advantage though. That Leeds-London train takes a tad over 2 hours, while the bus is more like 4.
The entire "privatised" monopoly train system is ridiculous though. I'm dreading the day I turn 26, because it will basically mean that I can no longer afford to travel by train.
The train worked out at £40ish each way (I didn't know I was going till a couple of weeks in advance, if it had been months I'm sure I could have bought tickets for less).
Using Megabus, I paid £4 to get there, £8 to get back ... and then had to pay £9 to get a taxi from the city centre to my house.