We (my wife and I) were able to live off 30% of our post-tax income, not because we wanted to live in poverty, but because we made a lot of money. We did live frugally, drove older cars, ate out only 1-2 times per week, cut cable and replaced with hulu+netflix, and bought a small house. However, I also bought a new phone essentially every year, a new laptop every 1.5 years, and took nice vacations.
The key here I think, was avoiding "lifestyle inflation" when we got raises and things like that. That extra money went straight into savings. We don't even follow a budget, we just save "a bunch" and then live off what is left, if the bank account is still increasing in size after that, we save more. We save most when we feel like at the end of the month the bank account our checks go into will be close to zero, this scarcity prevents us from spending too much.
If you work in tech and your spouse works, it isn't a far stretch to say many here are making over 150k/year. At 150k, say 30% for taxes and say you start living today off 45% of your post-tax saving, that give you 47k (after tax dollars) to live off of (and a savings rate of 57k/year). If you can manage this, you can retire in 20 years.
Median household income in the US is 50k (pre-tax), so I find it hard to believe that you can't get by quite nicely on 47k post tax. True, in many places the cost of living is higher, but you're probably earning more than 150k in those areas anyway.
Saving like this isn't going to work for everyone, but if you're making a lot per year, you should be able to swing living like a "median" American for a few years to boost your savings.
EDIT: I thought I'd also mention that you don't need to wait until you retire to enjoy life either. My wife and I quit our jobs last year to travel for 8 months through South America and Europe. That isn't such a scary prospect when you're able to save large portions of your income to help fund the travel and a sizable cushion for returning home.