I landed a contract from an advertising company. It was an interesting job and they were paying good money. The weekend after I was hired, I was watching a broadcast of a four hour event that I cared about, only to have it interrupted every 15 minutes by 30 seconds of the most obnoxious advertising imaginable.
When I looked at the HTML, I saw that the advertising was delivered by the very company I was now working for. A clear message. I left the following Monday and never invoiced them.
So today I went to use a web e-mail service and there was a funny little video about a weatherman who had an on-air rant. I clicked it and 30 seconds of advertisements were queued up. I clicked away.