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].
It is sad to know that. Couldn't google have bought the company altogether. Also how does this compare with imvu and snapchat (the two companies I know which didn't get outright killed because big companies tried to copy their product idea and failed)
Go back a bit and you will see that corporations like Microsoft (and many others) are built on stolen ideas. Its a very long list but Lotus123 and Netscape spring to mind for me
[0] https://www.crunchbase.com/organization/kiko#/entity
[1] http://paulgraham.com/notnot.html