This is a build on Riven the Exile. I've done a lot of experimenting and testing and this is what I've come up with.

Any questions add Ansayru on NA.

Everything is currently under construction.

9/15/2011: Added guide to MOBAFire.
9/15/2011: Added more items and item chapter.
9/16/2011: Changed items, and skill sequence chapter.

Important:

Early Game:
Get 2 Doran's Blades, HP pots, boots of your choice.

Only sell your 2 Doran's Blades when you need the space, or you have a big item ready, but you don't have the little amount of gold you need.

Core:
Doran's Blades x2, Boots, Wriggles Lantern, and Phage.

Mid Game:
Frozen Mallet and Bloodthirster

Late Game:
Clean it all up with Infinity Edge and GA.

If they don't have a lot of CC get Ionian Boots of Lucidty rather than Merc Treads.

On to the topic of skill sequence. Personally I believe that broken wings is completely useless unless you max it first. Reason why is that at level 1 it only does about 30 damage, per hit. At level 5 it'll do more than 100 damage per hit, and that is at only a little bit past level 6.
Or instead of just straight maxing it, you can stagger it with Ki Strike. Also a good option.

GET VALOR LAST! You don't need it first. With your wriggles it should give you enough sustainability in lane for a good amount of time. I don't think the shield on Valor is worth it, too too early, because it takes away your damage. This is my opinion. You are free to max Valor first if that's what you believe should be first.