blackmarket arms.
marmite.
Rush CDs
Cowboy Mouth CDs
Harry Turtledove non-fantasy books
tools. Of the Craftsman kind.
CD’s from my local bands
Shirts from said bands
Black eyeliner/ eyeshadow
Red lipstick
Any clothing that’s black and tight and fits (I’m really tiny, but 6 feet tall as well so this is rare)
Besides the items required for proper personal hygiene…anything by Neil Gaiman.
Elvis Costello CDs
Orson Scott Card books
Turnip twaddlers
Sunflower seeds.
And Pocky!
[sub] I love living in Hong Kong [/sub]
A three stooges talking bottle opener
Any Pez dispensers featuring the better Cartoon Network characters.
I’ve yet to see them, but you can be sure I’d snap up a Johnny Bravo or Samurai Jack Pez dispenser if I found one.
Then I’d bring them to school, sit in the front row, and prop them up on my desk. Facing the professor.
I second tools.
Funny, I saw the thread title and came here to post exactly what Lobsang did. Of course, if I had thought about it a minute, I should’ve known what he’d post in advance. Duh … 
Just to also tie this back to the OP, UK paperback editions of new Terry Pratchett novels. And they gotta be the UK versions, just for the cover art. Once I get a real bookcase in the living room, I’ll move my collection to hardbacks. 
(And I wish I could say “new computers” 
)
For almost every one of Mr. Pratchett’s books, I’ve wandered into the bookstore on just the right day, not knowing the book was coming OUT that day, and seeing it in the fantasy section.
Grab. Buy.
But this time, I know it’s in the store, and I’m not getting it. Why, you ask?
-
I’ve already read it. Got the reader’s advanced copy. I highly recommend it.
-
I’m going to buy it when he COMES TO MY TOWN FOR A SIGNING!!! To my second-favorite bookstore, no less.
I have standing orders at Amazon and Amazon.UK for every new book by Pratchett and Holt. No hesitation.
Any of the rarer Frank Herbert books. Not easy to find, I’m browsing the amazon.co.uk z-shops at the moment. Two incidences of luck, so far.
Also, Pratchett’s books. I can’t wait till his signing, comming soon!
Sweets for your tooth?
Definitely soap too.
Jewelry, handbags, meat, and cheese.
What do I buy without thinking twice?
Clothes-Has to be black
shoes anything that resembles a shoe I buy
Almay Black Eyeliner-in bulk!
Purple lipstick
Stocking of all designs and patterns
CD’s
Any little gadgets to put on my desk to entertain myself at work
Good cheese
Lip balm
Funky socks
Cool pens
Fortunately, most of impulse-buy items aren’t too pricey.
People have mentioned essentials like nappies and bog-roll.
Those things require at least one thought - “Do I have any/enough?”
I am talking about things that we don’t even think a single thought about buying.