We talk a lot about deals on this blog (hence the name), but let's get philosophical. How do you decide if something is a good deal? Does it need to be at least 30 percent off? Fifty? Come with a free lipstick?

Here's how I do the math: At the end of the week, after there's gas in my car and food in my fridge, I'm left with a pittance of disposable income. I could take a break from brown-bagging my lunch and eat out for a change, or I could spend the surplus on some retail therapy.

Now, I love me some Chipotle, so when I treat myself to a meal out, it's often a chicken burrito with pinto beans, chili-corn sour cream, cheese and lettuce, hold the guac. With a drink, that comes to a little over $8.

Thus, if an item of clothing or jewelry is on clearance for around $8, then to me it's a no-brainer:

Chicken burrito ($5.95) + bottled water ($2.10) = pair of earrings ($8.05)

Chicken burrito ($5.95) + Nantucket Nectar ($2.40) = new dress ($8.35)

Who cares if the earrings will be passe by fall? So what if the dress falls apart in my washing machine? If I get one use out of it, then it passes the Burrito Test. It's not like I would've eaten the burrito more than  once anyway.

My rationale may seem unusual, but I think we all have one. Divas, how do you decide how much is okay to spend on an impulse buy? Is it the price of a Starbucks latte? The cost of getting your nails done? The change you find in your cupholder? What's your Burrito Test?

~ Deal Diva Dalia

(Photos: Would you rather eat your money or wear it?)