Wow Muppity - that's a huge amount of willpower your friend has to stick to that (supremely low) level of spending for 4.5 years. I reckon you did help out by shouting the odd coffee here and there!!

Lizh's post reminded me - I also have a little over half of my fortnightly pay going directly off the mortgage. It really helps to never see that money in my own account and just live off what is left.