Two things.

One thing that really annoys me is the list at the beginning of every cookbook that tell you the things that you MUST have in your kitchen.

Things that I am told I MUST have, but have managed quite well without:
1) a slotted spoon (use a fork or a regular spoon people)
2) a set of mixing bowls (mostly what bothers me is that they give you a size requirement, you know any number of sizes will do, I use my salad bowls and soup bowls and cups depending on how big a mixing bowl I need)
3) kitchen tongs (I'd like tongs, I really would, but a fork and a spoon have done me well over the years)
4) ruler (this is just plain stupid, almost nothing needs to be exactly measured this way and only encourages budding cooks to be overly anal)
5) pastry blender/knife (use your freakin' hands)
6) spreader (as in a thin flat spatula) (use a freakin' knife)
7) custard cups (use your damn water glasses)
8) rolling pin (this is actually something I'd like to get, some day, but a bottle works really well)
9) egg separator (use your freakin' hands if you can't figure out how to use the egg shell!)
10) melon baller (yes, this was listed as a must have and I have NEVER EVER needed one)

The second is the assumption that you have other obscure things as well.

1) double boiler (without fail it is not mentioned in the list of must haves, but always turns up in the dessert recipes)
2) parfait glasses (unless you were married with 300+ guests, chances are you do not have a set of these hanging around your house)
3) local [insert foreign place name] specialty store (my California cookbook is very guilt of this, unless you live in San Francisco, you probably don't have a local asian specialty store)

There are, IMHO, only two things that you really really need to have in order to turn out a meal in your kitchen.
1) water heater
2) the internet

From making a pot of tea to oh-shit-I-don't-have-enough-boiling-water-to-cover-the-pasta, the water heater is in use in my home almost constantly. At least once a day. Back before we got a coffee machine, this is also how we made coffee. Yeah, you could point out that I could have boiled water in a pot on the stove, but I say to you, HA! With a water heater I can make coffee and instant soup NOWHERE NEAR A KITCHEN STOVE!! Yes, ladies and gentlemen, you don't actually need a kitchen if you have a water heater. That makes it the number one most important thing you may ever own in your life - and you read it here first. Unless someone else said it first on some other blog, but you know, I do not have time to scour the web looking for precedents.

The internet can also save your butt in the kitchen or... get this... give you recipes for things you can make in your water heater WITHOUT a kitchen! It also gives you regular recipes, including a handy search option (I google) to find recipes for, say, all that red cabbage you suddenly have in your refrigerator. Realize you can't get creme fraise in a hundred mile radius from your house? You can find a substitution on the web! But hands down the most important thing the internet can do for you in your kitchen is answer that age old question "you want me to do what with the what?" We all know how to steam veggies (well, except for my dear Dane, but that's another post), but the first time I was asked to reduce the drippings to one half? I took half of the drippings out and poured it down the drain. Lets not talk about that moment, okay? I was also stumped with "deglaze the pan with some wine" the first time I saw it. This is why cooking blogs were invented and I am extremely grateful for everyone who has ever posted how many grams are in a tablespoon of butter (14g btw).

The down side to the internet and cooking blogs is that you may suddenly realize you are not the chef you thought you were. This becomes readily apparent when you are looking for something to do with your left over red cabbage and discover that someone else had the same problem and so just whipped up a hot and sour soup with it. Completely pulled the recipe out of their ass and presto! Brilliant soup.

Me, a throw a bunch of leftover broccoli, an egg, some milk and a bunch of cheese into a pan and try to cook it. Lets just say it would have made a great quiche had I only put it in a crust. As it was... well, it was pretty tasty, if you like salty green mush, but nothing that I would make anyone else eat. Gah! If only I had thought "gee, this might make quiche! I should put it in a crust and bake it!"

Next time I will totally google the shit out of that.