Update: these came through the very wet winter of 2013-14 on heavy Wealden clay, so look like being very tough indeed. Not tried them with wet and cold yet.
1L pot ~ £6
Arthropodium candidum maculatum
A more familiar plant in European gardens, this is a tiny New Zealand version of the above. The overall effect is of a small grassy tuft with tiny white flowers on short thread-like stems. The foliage though, as with so many New Zealanders, is the real feature, being a rather cryptic mottled coffee brown.
Intriguingly pretty, but grow it in a trough or raised bed or you'll forget it's there.
Closely related to milleflorum but with larger, more deeply coloured flowers. I've not tried it unprotected in the open garden yet but this is another common and widespread species in eastern Australia so worth a try in a sunny well-drained spot outside. The locals call it the Chocolate Lily. I'm not sure why. It doesn't seem to be scented.