Miss Fortune Build
Not Updated For Current Season
This is what I use with Miss Fortune, for maximum ganking power AND survivability.
I usually take middle lane and use Make It Rain relentlessly. Very few champions can counter MF's pushing ability early game. A lot of people who write up builds forget to mention one of MF's most awesome strengths...the ability to kill enemies BEHIND towers. Use Make It Rain and then run back out of the turret's range, or if they have low health you can use Bullet Time from outside the tower's range and still hit champions that are behind it. If they are at low health bullet time or make it rain can kill them when they think they're safe. PLAY AGGRESSIVELY, there's a reason you bought 2 health pots to start with.
I take impure shots as my second ability choice because I use the bonus attack speed to get the most damage possible in on towers while i have minions to soak up the damage for me.
Once the middle tower's pushed over I generally go ganking on whichever lane my team is having trouble with. Hide in the brush, activate impure shots, make it rain on their heads, and run in.
After this point it depends on how the overall game is going for you to decide how to play.
I grab basic boots first because MF is soooo squishy when she looses her speed buff from getting hit. Then build phage for some more health and the 25% slow helps gank. Grab berserker's boots next to make phage hit more often and then spend the big bucks for your FM. By this point you're gonna need more damage to keep up with your opponent's defense so get the BF Sword and then make it a Bloodthirster for more survivability. Attack speed's your next goal so get yourself a zeal, and then up to phantom dancer.
Usually by now my team is winning pretty hard. I just stack on the damage with infinity edge or if my opponents have a lot of armor i get the black cleaver instead.