I have two things on that list, one if which is tangential to Woodworking
A versatile wide-band bandsaw, I would like to own one, if I had space... but a big part of me would like to build one; i've been increasingly drawn away from woodworking in the last year to machine maintenance/rebuilding/upgrading and this idea fascinates me.
Based on everything I've learned, they're relatively simple beasts, but by necessity big with rather substantive straining forces applied; which demands real attention to detail in achieving effective alignment of the wheels when tensioned.
A timber framed house, might be traditional oak framing, or modern engineered timber methods; but a lifetime of being shown all the most amazing bits of contemporary timber construction has sold me on it, and I'd really love to do it off my own back as much as I can.
I'd also (and this is something which I can be more certain of being achievable without considering external factors) like to build a set of curved leg chairs... The challenge is not in making one (well it is, as that's no mean feat), but a set which match identically; I reckon there must be a good 5-8 years work and many mismatched chairs in learning to do that.