For me, Halloween has always been a homemade holiday. We always made our own costumes, created our own tree-ghosts, carved our pumpkins with frighteningly dull knives from the kitchen, and put together our own haunted houses. In fact, I don't think I had ever set foot into a Halloween store/kiosk until a year ago, when I strolled in to find a cheap costume for an office party, only to find that my costume choices, as an adult female, were limited to Naughty Nurse, Dirty Kitten, Slutty Bunny, and a host of other sexualized forest creatures or blue-collar occupations or icons (there's actually a Statue of Liberty costume that includes garter belts).

What a disappointment! As someone who enjoyed a childhood dressing as an Arab merchant, gypsy fortune-teller, flapper, super-hero, Alice in Wonderland (the non-slutty version), spider or Killer Bee, I was pretty certain that I could do better on Halloween than merely exposing a bunch of cleavage. Hey, that's what everyday life is for - I like my Halloween to be less boobalicious than that. 

I settled on dressing as an undead thoracic surgeon (that's me in the above pic). I was working for a company that designed medical software, so it was topical. My office mates and I purchased some cheap pajama bottoms for scrubs, covered ourselves in 99-cent red lipstick and dark eyeshadow, and lurched around terrifying our coworkers. It was great.

It taught me that the trick to a fabulous costume is really all in the attitude and originality. If you FEEL scary (or cute, or crazy), people will be genuinely impressed with your spirit. Also, there is nothing more pleasing than getting compliments on something you put together yourself.

The simplest materials can net the biggest return, as in some of the examples below:

Yards of material/old white sheet

The old white-sheet with holes cut in it trick still works pretty well, although a more diaphanous material than cotton sometimes works better. Togas are a simple costume, allowing you to go from Edith from Accounting to Julius Caesar (bloody holes in the costume), Sappho (be creative), or Socrates (white beard and hair, pensive expression).

Gwen Stefani recently attended a costume party dressed as a fried egg, in what I believe would be a fairly simple costume to create at home with some white and yellow felt and hot glue (her husband went as bacon, but there don't seem to be any good photos of this).

Mummy costumes are extremely easy to accomplish, given an old white sheet and a pair of scissors.

Cardboard

Cardboard boxes are probably the best thing ever invented by man - never has a more versatile shipping container been seen in the history of mankind. It can occupy your kids, thrill your kittens, and makes for a great basis for many a Halloween costume. You can be a truck, Lego block, popcorn box, or.. well, I'm not sure what to make of this one (nominally NSFW).

One of my favorite people in the world went as his own Facebook profile last year (I LOVE the ideas on this blog - Cereal Killer, get it?). This year, I'm planning on going as a tombstone - very few things are as easy as a sandwich board costume. I imagine that iPhone costumes will be ubiquitous this year; you could always go dressed as the G1 and challenge all the iPhone-costumed people to a fist fight.

Fake Greenery

Far from being limited to home decor, fake plants, silk flowers, and foliage can make for some adorable and fairly easy homemade costumes. Fake flowers can be expensive, but almost every craft store has a section for flowers that are "out of season".

My dogs are going to be dressed as pumpkins this year, but why not consider a Chia pet outfit for your pooch?

Loads and Loads of Puffy Materials

This smart lady came up with what I think is my favorite Halloween costume of all times - a bath scrubby. I'm particularly fond of the ease with which one could become cotton candy. Pumpkins are easy costumes to create, as are tea bags. I'm personally in love with the idea of going as a bag of jelly beans, except that I have a mortal fear of balloons popping, but I've considered using those cheap, swirly rubber balls and dressing as a bag of marbles.

Paper Mache

Paper mache takes a good deal of work, but if dressing your child as a California Roll isn't worth hours of your spare time, I don't know what is (although some of that is technically upholstery foam, I guess).

Misc Ideas

The year that I dressed as a surgeon with a taste for flesh, two coworkers down the hallway dressed up as the Blueman Group - they wore blue sweats, blue swimcaps, and blue greasepaint (they won the office costume party). I've had great success as a bride before - old, tacky bridal gowns are easy to find at thrift stores, and there are plenty of variations of bride: the left-at-the-alter bride, the 80's bride, the bride who decapitated her groom and is carrying his head around... the possibilities are endless.

There are some some good ideas for humiliating your children before they are old enough to realize it, including my personal favorite, a baby Chippendale's dancer. And of course, there is nothing that duct tape can't do.

A plethora costume ideas (without pictures, but with instructions) can be found here. Guide Spot has some really good ideas for easy homemade costumes. Coolest Homemade Costumes has some incredible reader-submitted ideas, as does Costume Works. I like the quick-n-easy punny costumes listed at Costume Idea Zone, too. Group costumes are always fun (Japanese tourists are a fun and easy one to mimic without having to purchase much of anything - knee socks with brown sandals, button down shirt, shorts, goofy hat, possible black wig, glasses, and your fingers raised in a permanent peace sign).

Please feel free to share your favorite costume ideas in the comments!