Open Friday: Highly Anticipated But Delayed Gaming Products

Owing to some technical issues, it looks like the Dwimmermount Kickstarter won't go live today, though you can view the preview of its page here, if you'd like to see it, including a piece Jeff Dee did for the book's back cover (the front cover, by Mark Allen, is almost finished as well). Rather than vent my frustration at this unexpected turn of events, I thought I'd turn it into an occasion for an Open Friday post.

So, here's my question: what are the gaming products you most wanted to see released over the years but were delayed again and again -- perhaps even to the point of never coming out? For me, I think the big ones are Gary's Castle Greyhawk and City of Greyhawk products, about which I've talked before. What are yours?