Love of His Life by julad, QaF, Post-Season Three, Brian/Justin, others.
In the hands of an extraordinary author, there's really nothing more fun than cliche-fic. It's so good, and so fun, and an intensely *Brian* characterization, and it never goes where I expected, and--yeah. *Happy*.
This reminds me I need to update my recs page sometime this month. *sighs*