JASON: dark clothes, tattered coat, goalie mask, and fake machete.
DARTH VADER: buy Darth Vader mask and make the rest yourself. For "life support" panel on chest, use anything electronic looking, like a circuit board. If it's not black, paint it to make it realistic. If you can add flashing lights, even better. For hands, use big black gloves for "crushing hand" effect. For cape, use any long, flowing black cape. As for Vader's "jumper," the look of padded life-support suit can be done with black jumper and creativity.
DARK KNIGHT: tough one, but many stores are out of this costume so here's one to try. Wear black pant suit with long sleeves, which can be done with sweats. For best effect, wear black sweats and silky black thermal top and bottom (like the kind at Target) over the sweats (sweats add bulk and thermals look better than sweats). Next, add chest armor, which you can buy or make out of cardboard. Chest plate should have batman logo on it. Then wear black gloves and, if you can, black arm bands that cover from wrist to elbow. Next, add utility belt with gold buckle, black boots (check thrift store or improvise), and black cape (buy or use black sheet). Finally, the mask. If you can't buy one, make it out of tri-hole (holes for eyes and mouth) ski mask by cutting area around mouth to be bigger and adding bat ears with black felt or cardboard.
DARK KNIGHT JOKER: spray temporary green color in hair. Apply white face paint in messy, uneven manner. Ring eyes with black shadow and give it messy, smeared look. Furrow your brow and trace the creases in it with brown eyeliner. To do an "acid burn," glob Elmer's glue around mouth and partway up cheek in pattern of Joker's scars. As glue dries, move mouth around to give glue a puckered effect. Once glue dries, it'll have flaky, dead-skin effect. You can apply more glue as you see fit to get desired effect. Smear on red lipstick in messy manner and extend corners of mouth upward with red lipstick and even into "acid burns." Then dress in a grey and black patterned shirt, green patterned tie, green vest, purple (or as close as you can get to purple) jacket and pants, and old shoes. Note: some people are allergic to glue so be careful when using it on skin and never get it too close to your mouth.
PIPPI LONGSTOCKING: wear crazy mismatched clothes and socks and black boots/shoes. Put hair in braids and run wire through them so they stick out. Paint on freckles with eyeliner and black-out a big space between front teeth. Additional: carry a suffed monkey with little straw hat on.
ROSS PEROT: wear a suit, big ears, big nose, and slicked back hair made to look grey. A "Ross Perot for President" shirt is a nice addition under the suit.
ALEX FROM A CLOCKWORK ORANGE: derby hat, white pants, button up white shirt, boots, painted black cane and one false eyelash, heavy on mascara.
THING FROM THE ADDAMS FAMILY: dress all in black exept for one hand.
ADAM AND EVE: wear flesh colored bodysuits, cut leaves out of green felt and attach them to bodysuits with safety pins. Don't forget the apple!
LAUREL AND HARDY: for two people. Both wear old suits and bowler hats. The person who is Laurel wears a bow tie and the person who is Hardy wears a straight tie, black moustache, and stuffs their clothes to make them look fat.
HANS AND FRANZ FROM SATURDAY NITE LIVE: wear grey sweats stuffed with pillows for bulging arm and thigh muscles and wide tan belts.
NEIL GAIMAN'S SANDMAN: you need white facepaint for face, black paint for look of having sea of black for eyes, dress in black trench and black clothes.
SCARLETT O'HARA: wear gaudy bridesmaid or prom gown, do your hair in curls and ribbons, and carry a fan or parosal. If you have a date, have him go as Rhett, wearing a (stylish old) suit, coiffed hair, and moustache.
JULIUS CAESAR: wear sheet as toga, sandals, wreath of leaves on your head.
THE CROW: wear black clothes, black trench, black boots, and long black hair. Paint your face white and add black make-up to eyes and mouth (look up photo online to see exactly how the face make-up is done).
EDWARD SCISSORHANDS: wear black clothes with silver accents, messy black hair, and make you face pale, the area around your eyes dark/hollowed, and lips black. Then, cut out large cardboard scissor blades (fingers), wrap them in tin foil, and use silver duct tape to tape them to a pair of gloves.
VILLAGE PEOPLE: for group. Go as The Village People: police officer, Indian chief, cowboy, construction worker, biker, and military man.
CLUE: for group. Dress as characters from the game Clue: Colonel Mustard, Miss Scarlet, Professor Plum, Mr. Green, Mrs. White, Mrs. Peacock (and Mr. Boddy, if you like).
FAT AND LAZY SUPERMAN: wear a Superman outfit, stuff it with pillows so you look fat, and don't shave for a few days. If you go to a party, ask people if they need help with the food on their plates or their drinks.
NOT ROBERT PALMER: for group. Have one person dress like golfer Arnold Palmer and a few other people go as golf caddies that are dressed like the "Simply Irresistible" girls in the Robert Palmer video. Most of what you'll need for the costumes can be found at a thrift store. Don't forget the golf club!
TIM CONWAY: doing his shortest golfer and shortest tennis player characters. Stick your legs into big boxes covered with astro turf up to the knees. Put shoes at the knees on top of the boxes, cut a golf club short and cut a tennis racket short and wear appropriate clothing for the sports.
PHANTOM OF THE OPERA: wear black clothes and a black cape with hood. For the mask, just buy a cheap, clear mask, paint it white, and trim it to look like the Phantom's.
FLAVOR FLAV OF PUBLIC ENEMY: Adidas suit, big clock on gold chain around neck, white frame sunglasses and baseball hat worn askew
JOHN AND LORENA BOBBITT: John wears pajamas with fake blood on the crotch. Lorena wears night clothes also, brown wig, and carries a bloody knife. And, if the party you're going to is for grown-ups, Lorena can also carry a hotdog, if you know what I mean.
MADONNA REED: a housewife with a wild side. Simple shirtwaist dress and pearls, like Donna Reed. And Madonna pointy bra on the outside with Madonna hair and make-up.
ALFALFA FROM THE LITTLE RASCALS: dark high water pant suit and hair parted in the middle with lots of Dippity Do and Alfalfa's trademark piece of hair sticking up in the back.
NANCY SINATRA: blond wig, short 60s style skirt and black knee-high boots.
TAMMY FAY BAKER: bouffant hair and ten tons of make-up, complete with runny mascara.
DAVID KORESH: get an old shirt and pair of jeans. Torch them so that they're burned but still intact. Cover parts of body not clothed with black paint to make it look singed. Paint hair black and frizz it. Carry singed Bible. When asked who you are, say "Christ the destroyer of Babylon" and "David the destroyer of Babylon."
CARRIE: wear old white prom dress from a thrift store, lots of fake blood, and carry a bucket of red jello.
RICO SUAVE: dress like a Lounge Lizard.
JAMES DEAN: jeans, white t-shirt, coiffed hair, and cigarette.
KRAMER ON SEINFELD: high waters, wild shirt, thick eyebrows, funky shoes, big hair.
STATUE OF LIBERTY: use gel to mold your hair into points, wear a sheet, and carry a book and a flashlight.
FORREST GUMP: wear a plaid shirt, suspenders, and carry a box of chocolates.
HOWARD STERN: wear round dark glasses, dark curly wig, gold chains, jeans or leather pants, and lots of attitude!
ANDY WARHOL: wild platinum/white hair, dark glasses, and black turtleneck. Carry a can of Campbell's tomato soup and a paint brush for added fun.
PAT: (from SNL) wear tan pants with a men's belt and blue button down shirt and stuff the pants/shirt to make yourself look pudgy and hide any breasts if you have them. Then add black horn-rimmed glasses and a short, dark curly wig (or wear your hair as androgynously as possible). The point is to make it impossible for people to tell if you're male or female.
Robin Hood: wear green tunic with thick belt at the waist, green tights, and a Robin Hood style cap. Add a fake knife to the belt and carry a bow and arrow.