I was extremely eager to get out of my then-current employer, so the situation became extremely stressful to me. I didn't want to burn a bridge with my then-employer and wanted to give them a full two-week's notice.
Eventually I'd had enough of waiting and gave them my resignation before I worked a single day, even though I was supposedly an employee (went through full handbook, tax stuff, etc). This was on a Friday morning. The full rest of my day was them calling me over and over convincing me that they could start me the following Monday.
I still walked -- not worth that kind of disorganization and hassle. I'm convinced that the whole time I wasn't working they were billing the client for me to be there. ...They paid a lot of money for my background check too... whoops!