Zerg v Protoss: 12 Minute Roach Max

This build focuses on heavy macro with an early third base, heavy droning followed by mass roach till you are maxed out with a speed roach/zergling push to follow. The power of this build lies in the ability to create a maxed out army very early in the game in which you are able to continue to macro and tech up to infestor/broodlord or another composition of your choice and if you lose your army you have the ability to remax very quickly. Key timings are highlighted in red.

5 - Spawning Pool
16 - Queen
18 - Zerglings x2
20 - Hatchery (2nd)
19 - Drones x2
21 - Hatchery (3rd)
20 - Queen
22 - Overlord

From here on you want to make as many drones as possible while scouting the protoss' base with overlords as well as continued zergling scouting around the map for hidden pylons. Don't be afraid to make zerglings, spines, queens or spore crawlers if you scout aggression from the protoss player.

22 - Drones x7
29 - Queen
31 - Overlord
31 - Drones x11
42 - Overlord
42 - Extractor x2
40 - Drones x4
44 - Overlord
44 - Drones x10
54 - Roach Warren
53 - Evolution Chamber
52 - Drones x6
58 - Overlord
58 - Drones x10
68 - Queen
70 - Lair
70 - Extractor

From here, it is almost impossible to make too many overlords. You are shooting for 200/200, so feel free to make multiple overlords at once.

70 - Overlords (many)
70 - Roaches x10
90 - Extractor
90 - +1 Missile Attack
90 - Roaches x10
110 - Roach Speed
110 - Hatchery (4th)
110 - Overlords (many)
110 - Roaches x20
150 - Zerglings x20
160 - Hatchery (macro)
160 - Overlords (up to 200)
160 - Roaches x15
190 - Zerglings x20

Move across the map and start to be aggressive against the protoss natural but don't overcommit because there is a huge risk of getting trapped in forcefields. From here feel free to tech up to your choice and add spine crawlers at key chokes and bases as well as reinforcing your roach zerling force in the attack.

Zerg v Protoss: Early 10 Roach Push

This build is an aggressive roach/zergling attack designed to destroy protoss opponents who go for the forge fast expand build. The attack hits early at around 7:20 before any major protoss tech has completed and if unscouted should do sufficient damage or win the game outright.

09 - Overlord
14 - Extractor
14 - Spawning pool
15 - Overlord
15 - Queen
17 - Zerglings x6
20 - Zergling speed

Remove Drones from gas, but then return them once the scouting Probe has left. 

It is critical from this point out to deny scouting information. Use your six zerglings to control Xel'Naga watchtowers, watch the entrance to the protoss' base and constantly scout for hidden probes and pylons.

20 - Hatchery
19 - Drone
20 - Overlord x2
20 - Roach warren (around 4:25)

Cancel the hatchery when Zergling Speed is completed (around 5:20)

20 - Roaches x10 (around 5:45)
40 - Overlord

Remove all drones from gas

40 - Continuously produce Zerglings from this point

This build is very dependent on denying all scouting information which your opponent possesses. If the cancelled hatchery or early roach warren are spotted the protoss has a chance to produce additional units and cannons which severely diminishes this builds chance of doing damage.