Reader G.W. Smith points us towards this adorable little Portal headpiece, which can help the ladies (or long-haired gentlemen!) look like the villainous GlaDOS is sticking out of their scalp.
The ornament was made by Luke Walker. What I like about it is how weird it is. It's not just turning an existing thing like a headband or regular hairclip into sometihng with a bit of Portal guff on it. It's something weird, novel and unique.