Ryanair makes it possible for a work colleague of my sister to commute from Cork to Liverpool (4 day work week, digs while in Liverpool). You get what it says on the packet.
My wife and I once flew the length of the UK return for under £4 on one of their sales deals.
No typo there, under £4.
And I used to commute Glasgow to London once a week and would regularly pay for for the train from the airport to the centre of town than for the flight.
And if you take the train from London to Glasgow, it is currently £120 for a single ticket, whereas I can book on British Airways for a flight tomorrow for £74.
Should probably be a bit fairer to the train as you can get better deals than that and pay a lot more on BA. I've paid £80 for a first class return and I've paid more than £250 return on BA (both London - Glasgow).
But yes, the train can be terrifyingly expensive if you can't pick and choose your time (though I also find it more productive - no putting away your laptop for take off, no security, just sit down and do stuff).
