I get a particular negative jolt when I review a credit card bill and find a charge for something that's already over and done--a meal already eaten, a vacation already taken, a tank of gas already burned up. I'm much happier paying a charge when I can pat the thing purchased and know that it'll be serving some useful purpose for years to come. Just recently, though, I've found that I'm beginning to have a little more appreciation for those purchases that are only memories before they're even paid for.

Try this thought experiment: Imagine that all your property were destroyed in some disaster, but that you got a large check--replacement value for everything that was lost. How much of your property do you replace with exact duplicates?

A lot of the most important stuff is irreplaceable: art work, antiques, mementos of things you've done. You'd replace it with an exact duplicate if you could--and might pay top-dollar to do so--but mostly they're just gone.

A lot of the rest of it is stuff that you wouldn't bother replacing: that pair of old glasses that you could wear if you broke your current pair, those shoes that match the dress that doesn't fit anymore, that pot that you used to cook everything in before you married someone with really good pots.

Most of the rest are just things you have to replace simply because you need something to serve the purpose: a bed, some chairs, a table. No need to duplicate what you had--maybe you'd be better served by a bigger desk and a smaller car (or vice versa).

For me, this thought experiment puts a different perspective on my preference for spending money on things that last.

Sure, I'm very pleased with the bicycle I bought in 1983 and that is still my main transportation vehicle when the weather is nice. Its cost-per-mile at this point is so low it's not worth calculating, and it's still in near-perfect condition--I fully expect it to go another 25 years. But it's an exception.

Stuff that will last is great, but I've tended to put too high of a premium on that category.

Some of our best expenditures turn out to have been our vacations. We've been to science fiction conventions in Toronto, Boston, and Glasgow. We've been to Esperanto conventions in Berlin and New York. We spent a warm February week lazing about in Key West and a cool July week hiking around the coast of Wales. We took a cruise to Mexico.

And it's not just vacations fall into this category: going to college, going to concerts and plays, watching movies or videos, hanging out with friends at the coffee shop or bar. These also are experiences that may cost some money, but that may well be worth far more than, for example, a really nice leather jacket that would last for years.

For us, expenses of this sort have turned out to have provided some of the best value for the money we've ever gotten. Further, in the little thought experiment up above--what would you replace if you lost everything--they wouldn't need to be replaced: they can't be lost.

There are many reasons to to frugal--it's light on your wallet and light on the planet--but the most important is that it maximizes your freedom.

One way it does that is by giving you more career options: The more frugal you are, the less pressed you are to choose the most remunerative career (and the less pressed you are to stick with a poor choice simply because change would be risky--the frugal person can bear risks that others can't).

I was always in tune with that particular advantage of a frugal lifestyle. It's the one that motivates me most strongly.

What I've come to realize just recently, though, is that another advantage of a frugal lifestyle is that frugal people are free to spend the money they haven't sunk into stuff on experiences instead.

There are plenty of things you can do cheap or for free. But don't let the fact that an experience doesn't leave you with a useful object make you feel bad about paying for it.

Material purchases are about what you have. Experiential purchases are about who you are. After all, when people ask you about yourself, you don't tell them about your stuff; you tell them about what you've done.

On a personal note, I wanted to mention that this post marks my six-month anniversary of writing for Wise Bread. More by coincidence than plan, this is also my 100th post. I can't begin to tell you how much fun I've had writing these pieces. It's high on my list of experiences worth remembering. The photo is of me on the bank of the river Clyde in Glasgow, Scotland, during WorldCon in 2005.