The number one luxury I give myself is a good hair cut. A good hair cut can really cut down on the number of "bad hair days" you experience. I usually go twice a year because I ask for a cut that will keep looking cute when it is growing out. It costs me about $120 (including tip) when the appointment is over. I promise you, it is worth every penny!

I second straining your own yogurt! It's super easy and makes a container of regular yogurt more versatile. I found a set of yogurt strainers at a thrift store, but paper towels, coffee filters, or cheesecloth in a strainer work well. Plus you can mix the result with chopped herbs and spread it on crackers for a cheese effect. SO good.

Otherwise, for Greek-style yogurt that's cheaper than Fage, try Pavel's; for labneh (yogurt with even more liquid strained out), try the dairy case at your local Middle Eastern market.

I am a big cheapskate, so my only real splurges are on food and drinks.
- Good bakery bread is Always worth it.
- Single-flower honey from the farmer's market--usually they'll let you try the different kinds, so you can pick and choose! We have meadowfoam honey right now, and it is unbelievable. I think it was about $8.
- Sparkling wine: Chandon blanc de noirs, which runs from $15-18. It's not a huge splurge, especially compared to the high-end champagnes, but it's not like you're buying a $6 bottle of Cook's, either.
- Occasionally eating very good sushi at restaurants

Lush skincare. Okay I'm biased because I work for Lush but even after I leave and I no longer get the amazing staff discount, I will happily stump up full price for it. Nothing compares. (Plus it's not actually that expensive)
Dr. Marten boots. I have spent an irritating amount of money on boots that have worn out after 6 months. I fins it comforting that my Dr. Martens will probably outlive me.
Maple Syrup. It has to be real Canadian fancy stuff. Cheap maple syrup will not do.

Skincare: I buy Lancome products and it is worth every penny. Also, because they're more concentrated, you won't use as much as you would a cheaper brand.
Underwear: Nothing beats having a decent bra that actually lasts.
Shoes: I don't own very many pairs, and I will hang out and wait for that "perfect" pair that just keep on giving.
Getting clothes tailored: If I buy a pair of pants that fit my bum and thighs nicely, but gape at the waist, I'll pay to get that fixed - I've got a good booty and thighs on me, so if I buy the right size for my waist, chances are it won't even get up my leg. Also - if I buy a blazer that's perfect on my shoulders but loose all over, I'll get it tailored - I've got swimmers shoulders and big boobies, so I rarely find that perfect fit all over.
Makeup: if I'm going to get makeup, I'll buy it expensive. The formulas are nicer on my skin and last a lot longer.

So maybe I'm high maintanence...? but I've done cheap routes on all of the above and found it worth my time and money to spend up and get more out of what I pay for.

So, I am giggling about this one after reading everyone else's answers, but the only "must have" that I absolutely HAVE to have as name brand is Q-Tips! Cheap q-tips suck. They're usually smaller, harder, and just uncomfortable to use. I really wish I could like using the ones from our co-op, but I don't. I figure I make up for my Q-tip love in other ways, I guess. )

I agree with this so much!

I third the Q-Tips!!

Also Beer. I will pay more for flavor (Irish Death, please!).
And good fabrics (raingear, backpacks, sweaters).
Someone else cooking your food.
Plane tickets.
Reliable vehicle.
Vet bills (I write this as my cat is limp on my lap/left arm).

That said, I rarely pay full price for anything - consider it the only sport I'm good at.

*edit: the cat is HAPPY limp! Not dead or dying because due to neglect!!

I think I only spend lots on..
Shoes - clarks, birkenstocks or doc martens
Lush - solid shampoo and vegan conditioner
Vegan, rice milk ice cream - which is £5 a pot, but I'm vegan and have soya intolerance and sometimes I NEED icecream!

I'm a big, big cheapskate, but most of my money seems to go on eco-friendly stuff or organic food or stuff that's got recyclable packaging (if I was going to buy something and there was a cheaper version packaged in plastic or a more expensive version packaged in cardboard I'd buy the more expensive one...)

Definitely noticing a theme here:

bras - a good one can make you look thinner and younger. who wouldn't want that?

shoes - chaco flip flops are pretty much on my feet 7 months a year. worth every dime. also good? dansko clogs. because i'm sexy that way!

moroccan oil - styling creme and the oil - smells divine and makes my hair smooth and silky.

good hair cut and eye brow shaping - see earlier comment about wearing a good bra.

organic fruits and veggies - you are what you eat.