Chanel nail varnish - without exception the worst varnishes I own. Chip instantly even with proper base/top coat. Colours are nice but not worth it for the rage every time you glance down and think, "This, for £18?!?!".
Maybelline gel liner/brush - recommended by Lisa Eldridge as being as good as the expensive brands: it's not. Impossible to get a nice fine line with the brush and it dries up just as fast as the Bobbi Brown one. (Possibly because it is the Bobbi Brown one? Can't remember who owns who anymore...)
Nars Multiples - just made me look grubby
BB Shimmerbrick - just made me look as if I'd dipped my face in the chip pan
Liz Earle hair oil - instant greasiness
Boots No7 foundation so-called tester - dear No7 lady, I want a foundation that'll cover up my redness, not a foundation that will match the rest of my face to its reddest part, thanks.