[oblio]

Gmail was an acquisition, Google Maps was an acquisition, Android was an acquisition, Google Docs were an acquisition, I'm actually having a hard time thinking of a major Google project that's not an acquisition except for Google Search and Google Ads (and even there, I think they acquired DoubleClick early on and that boosted their ads business a lot).

[psyc]

All but gmail. That was created in house by Paul Buchheit.

[oblio]

Ah, I thought it was based on an acqui-hire of Oddpost: https://en.wikipedia.org/wiki/Oddpost

[jannes]

The Wikipedia article says that it was acquired by Yahoo and turned into Yahoo Mail.

You may have confused Google with Yahoo?