Virgin trains have just released their cheapest (£1) tickets for the London-Manchester route up until March 20th. Get in early to book cheapest tickets, trains only take 2 hours 8 minutes.
Just booked 2 return tickets for £8 total.
Please note guys, you MUST board the train at LONDON and MANCHESTER to use these tickets. Don't buy them thinking you can board at Brum and travel to Manchester, or Brum to London because they'll just wind up charging you for a new ticket.