I found an article at Girls Who Network, a blog for woman entrepreneurs, which talks about how to build a lifestyle to justify your desire to spend, spend, spend.

Their solution? Figure out what you want to spend, and then create an investment which yields that amount.

Your principal is your “golden goose”, the interest is the “golden eggs”.  You keep the goose and spend the eggs, forever!  As long as your goose lays eggs, you can have a shiny, new car parked in your garage.

For instance, if your desire to be in a new car every few years ends up costing around $6000 per year, you can invest $50,000 at 12%, and then the interest pays for your car without you having to work for it.

While I have a few minor problems with the theory (eg, what about inflation?) I feel that the idea is still an excellent plan and is far better, on the whole, than what most people do with their money.