I was glancing through the fragmentary information on the Starcraft alphas and betas recently, and I noticed a tendency for ideas that were scrapped in development to reappear in later games. So I made this thread so we can discuss examples of finding this.
In addition to the wiki, I have found the following sources on alpha/beta development:
Example #1:
Development: The evolution chamber was originally called "cerebrate" and the spawning pool was "chrysalis" (for reference, initially the zerg buildings would each produce larvae and in later development this was centralized to the hatchery, hence the idiosyncratic naming scheme of the zerg buildings generally sounding like it produces units).
Gold: In SC2, the new model of the evolution chamber looks a lot like a cerebrate, and the primal spawning pool produces a chrysalis around Kerry.
Example #2:
Development: During the SC1 beta the mutalisk had an acid attack and the queen had glave wurm, dark swarm and plague.
Gold: In BW the devourer is introduced as a mutalisk instar with an acid attack. In SC2, the viper is introduced as a flying unit with abilities similar to dark swarm and plague.
Example #3
Development: The scourge was originally an "avenger" which lived inside overlords and guardians and emerged when their hosts died, attacking whoever killed the host.
Gold: In SC2, zerg structures spawn broodlings upon destruction and the brood lord is a guardian-like flying unit that spawns broodlings.
Feel free to share your own observations.