There was a company called Kiko[0]. They made it into YC back in 2007 I think. They were basically building Google Calendar. After a year of work Google unveiled their Google Calendar and they had to sold their business. PG wrote about it in one of his essays[1].
[0] https://www.crunchbase.com/organization/kiko#/entity
[1] http://paulgraham.com/notnot.html