I'm going to go on since I haven't been ordered to shut up yet.
My makeup collection has shrunk over the years. It's probably worth only about $2000 now; at the height of my makeup-collecting frenzy I must have amassed over twice that sum's worth of products that I barely touched, and most of which I've since sold or given away. This is what I currently keep in my hostel room:

Back at home I have about another $1000 worth, but all backups - these are the items that I really use, either for my basic everyday face, or the ones that I reach out for when I need a little something extra.
My collection is for the most part made up of MAC, Dior, Kesalan Patharan, and Stila cosmetics, but that's not to say I don't use drugstore brands like L'oreal. I use whatever works for me, although my weakness for Dior is almost entirely based on the irresistable lure of the packaging.
This is what I use (more or less) on an everyday basis:
Concealer: Kesalan Patharan Undertone Lightup - I blend the orange together with the yellow in equal amounts on the back of my hand, then pat it onto my dark eye circles. Over this, I use MAC Select Coverup concealer for a natural finish that matches my skin tone. Finally, a dusting of loose powder (I prefer Becca, but this is expensive and not available in Singapore, so I've been using Kesalan Patharan's, which is also extremely good) to set. For any skin blemishes, I dab on Ettusais Acne Medicated Concealer.
Foundation: I'm a lazy girl so I just use a sponge and pat on some ZA powder foundation. When I need to look more polished for work, or for a night out, I use MAC Hyper Real Foundation (liquid, dries to a semi-matte finish) for skin that looks dewy, and then a layer of the ZA foundation over it. And unless I'm in a rush for time, I make sure that my skin is moisturised, so that the makeup glides on instead of looking patchy.
Eyes: I crimp my lashes with Shu Uemura's excellent eyelash curler, starting from the roots and then towards the ends for a more natural curl. For volume, length and definition, I brush on two coats of L'oreal's Double Extension mascara, using the black end only (using the fiber end just seems to make my lashes clumpy). For more defined eyes, I use a black eyeliner to line the outer half, starting with a thicker line at the outer corner and gradually thinning until it disappears at the halfway mark. This works for me because of the shape of my eyes, so if your eyes are shaped differently, another technique would probably work better.
Blush: I like MAC Sheertone Blush because it's very sheer, and if I want more colour, I just brush on more. Looks more natural than a streak of colour from a heavily-pigmented blush.
Lips: I'm addicted to Dior Addict lipglosses for now, but MAC lipglass is great too. I tend to stick to nude shades because I prefer to play up my eyes.
Finally, comparison pictures - an "everyday" face vs a "work" face (with more colours, but not really apparent here because of the stage lights):
ying @ 9:29 PM