Stuff I've re-bought several times:
Benetint (gone off it a bit now though)
Benefit Dandelion
Benefit Rollerlash
Boiing concealer
Double Wear foundation - Estee Lauder
Mac lipstick - Velvet Teddy
Clarins -
Red perfume
Handcream
The gold tins of hairspray - can't remember brand!
Aveda Hand Relief (I like this better than the Clarins, but the Clarins one smells better!)
OPI nail varnish
Urban Decay eyeshadows, especially the Naked palettes
Only bought once so far but will definitely buy again:
Mac Teddy eyeliner
Mac lipstick in Twig