What is your favorite portrait lens?

Probably posted about a million times before, but I want to know what you like as a portrait lens.

I have a Canon 20D with a 17 - 85 IS kit lens and a 70 - 200L 2.8 IS lens.

I love the "L" glass of the zoom, but it's bit long for portraits (especially with a 1.6 crop).

I think I want a prime. Been considering the 50 1.4 and the 85 1.8 but neither are "L" lenses, but the price is much easier on the pocketbook.

All comments are appreciated.

David