***EDIT***
Ok, It's 4AM, so I was playing lazy, and didn't care to scout too hard for dts, but here's a replay of it.
It's supposed to stop the usually collossi mass, and then give me map control, and the ability to tech to ultras/broodlords easily after that.
http://www.sc2replayed.com/replays/67809-1v1-protoss-zerg-metalopolis#rd:upgrades
***EDIT***
This is it against ZvT for practice.
http://www.sc2replayed.com/replays/67812-1v1-terran-zerg-steppes-of-war