Zerg rush?? you mean 6 pool!?
Now days zerg rushing is a core stratergy to any race. you build an offensive force that is your defense, very early you get a sort of critical mass in production that lets you pump out a steady stream of units. Its 'Noob' to build defensive structures rather than fighting with your units.
I often build some defense that could be easily overwhelmed by units but most of my opponents chicken out as they don't know how to estimate losses. In the meantime i use surgical strikes to disable their economy.
Back in SC 1 my main tactic was build 8 command centres and attach nuclear silos... then i would spread ghost along the edge of an entire base and launch one.
It would go something like this
<Nuclear-launch-detected>
<opponent- uses detector to kill ghost at front entrance>
<opponent> 'Haha NOOB'"
<Nuclear-launch-detected>
<Nuclear-launch-detected>
<Nuclear-launch-detected>
<Nuclear-launch-detected>
<Nuclear-launch-detected>
<opponent> 'oh smurf'

Usually with 4 ghost or so i could get a rollin g effect in that by the time the 8th bomb was hitting the 1st one was ready for launch
now days this is even more feasible, the trick is to hide the quantity of ghost academy you have in expansions in remote areas of the map.
Also loved SC1 when i used to play zerg, i pioneerd the 'zerg nuke' . Bassically i would mass zerglings and hydralisk to supply limit and put them inside overlord transports. Since there is no limit to the overlords you could have i would create literally hundreds and send empty ones in first. The cpu AI for cannons, spore cannons, turrets would naturally target them which meant the full transports at the rear came in unharmed. Finally the shear quantity of overlords would blot out the screen so my opponent had no way to rally his forces.
I am oftern accused of being noob in SC2 because i use my own stratergies rather than follow the latest rage of build order. I figure the people on grandmaster league do not consult the forums or youtube on how to win. The amount of times i have been told that i should of lost is staggering, people are very bitter in the SC servers.
Whats frustrating is i've been stuck in Silver lague since its release. I regularly get matched up with gold league opponents and beat them on at least a 50/50 basis or more. Started being matched up with the odd platinium player too, won several and the ones that i didn't were really close.
My claim to fame that i hold dearly was for Warcraft 3. About 4 years ago prior to the release of SC3 i was 147 on the asia server ladder. There where only 4 servers with some 60 thousand active players... so i think i did alright
