A couple of months ago, I shared some of the things I choose to spend my money on now that I’ve paid off my debts, saved for emergencies, and am funding my retirement. Most folks seemed to get my message: I cut back hard on the things I don’t care about (cable TV, clothes, newspapers and magazines) so that I can afford to spend on the things that do matter to me.

As I say, most people seem to get this, and understand that I’m not saying, “Hey you! Go spend a lot of money on whatever you want!” Because I’m not saying that. That’s not my message at all. I’m simply saying that if you can afford it, and if it’s something you’ll use and enjoy, there’s nothing wrong with spending on what you want — even if it’s expensive.

In fact, I’d argue that in some cases, the expensive option can actually be the most frugal choice. (The frugalest choice?) What do I mean?

Let’s take my physical fitness, for instance. As you know, I’ve struggled with both diet and exercise for decades. I’ve had success now and then, but mostly I’ve failed. And I’ve spent a lot of money to fail.

I’ve purchased weights and DVDs and exercise balls and gym memberships and fitness machines and fancy shoes and, well, a lot of Stuff. Most of this has been a waste of money. Why? Because I never use it.

I’m not completely stupid. Eventually I caught on that buying running shoes didn’t make me a runner, and that buying dumbbells didn’t give me muscles. So, instead of buying new Stuff, I started finding exercise equipment for free (or cheap).

For example, when my neighbors decided to simply give away their exercise bike, I took it. And when they gave away their other exercise equipment, I took that too. But you know what? I saved money, sure, but I was just as fat and sedentary as I always was — and now I had a lot more exercise equipment taking up space around the house. Free Stuff is still Stuff.

In April, I visited a local gym that uses the Crossfit methodology. (I’m not going to explain the system now — go read about it at Get Fit Slowly.) I tried Crossfit for a week. It killed me, but I loved it. It just felt right. It felt like something I could stick with. I asked how much it cost to join.

When the owner quoted me a price of $200 a month, I hesitated — but only for a moment. I signed up, and I’ve been paying $200 a month ever since.

Two-hundred dollars a month?!? Am I nuts? How can I possibly justify such an expense when other gyms cost $40 or $50 a month? Especially since I could do a lot of the Crossfit exercises for free at home? Easy. I’m okay spending $200 a month for Crossfit because it works.

I’ve lost 35 pounds this year, with more to follow. I’m stronger than I’ve ever been. I’m faster than I’ve ever been. I feel good. This is worth two-hundred bucks a month to me. Because I can afford it, cost isn’t an issue. In fact, I’d argue that this is a frugal expense because I use what I’m buying.

On the other hand, I have mountains of exercise equipment at home that I’ve bought and never used. (Okay, “mountains” is an exaggeration, but you know what I mean.) And all that free gear I got from the neighbor? That may have been cheap, but it wasn’t frugal. Cheap things you never use are no bargain! And something with a steep price tag can be a steal — if you get good value from it.

When you buy something, whether it’s an object or a service, ask yourself how much you’ll really use it. (And watch to see how much you actually do use it.) If there’s something you use a lot, it’s okay to pay for it, especially if it’s important to you. But I’d argue that if it’s an item or service you seldom use, you’re better off paying as little as possible.

Can you think of costly items and services that are actually good deals for you? Do you have collections of cheap things you never use? How have you learned to tell the difference?