Half + roll the rest is sort of cool, very similar to the way Iron Heroes does HP which I like.
d4 = 2 + 1d2
d6 = 3 + 1d3
d8 = 4 + 1d4
d10 = 5 + 1d5
d12 = 6 + 1d6
You can require the rolls be linked to the characters name on Invisible Castle, it'll do all the weird dice too.
Iron Heroes does...