Relapse 2. One of the biggest teases in rap history.
Release the original album, announce you have a sequel coming to the point where you put a skit about it on the original album ("What is this? Two CDs?!"). Let the critics shame you into not releasing the sequel, put out the original album with a couple new songs instead so people don't wonder where the sequel is, then announce months later there is no sequel and you have a new album coming.
I'll never understand this. It's not like Relapse 2 was supposed to be brand new material. It was just going to be more songs from the Relapse sessions, because Eminem and Dre recorded four albums' worth of material. Even if you're working on something else, just take the best stuff left over and make it Relapse 2, then put out Recovery a year later. Most likely, nobody pays attention to Relapse 2 but at least it still comes out.