Looking for a website which monitors email campaigns of famous companies

Thanks a lot everyone for your help! The website i was looking for was Inbox Flows http://inboxflows.com. It's a really useful tool that i highly recommend if you're looking for inspiration when setting up your drip campaigns.

You can also look at reallygoodemails and mailcharts

Sounds like an idea for a startup :D

Not sure if this is exactly what you're looking for but reallygoodemails.com and emaildrips.com collect examples of great email campaigns. Would obviously never advocate snatching copy, but they're good for getting inspiration and studying examples of good sequences :)