No the _worst_ is when they offer you the job verbally on the phone and in between the phone call and the written offer they give the job to someone else.
I can one up you. A couple of years ago I started looking for a job after a disastrous one. I ended up doing 3 interviews and a take home assignment for a UK company looking to relocate some people back to Greece and open offices here.
Then I went ahead and negotiated my salary.
Went ahead and stopped my job search after that and waited to be notified about my start date once the offices have been set up. Didn't follow up on a couple of other opportunities either because I was certain this was a good fit for me.
A month and a half later, after some pinging on my part, I ended up learning that the plans to open an office here were scrapped and I was welcome to work from the London office, as if I would feel comfortable moving abroad to work for an employer like that.