Me too, it's been a while since I was here on BCUK I missed the newer stuff. Looks like a great thread there and I shall read it with interest. My own "Cabin in the woods (with WIFI)" is progressing. of sorts. The main room is much more livable now and I can swing a cat without hitting too many breakable things. My added bit of good news is a neighbour with a big warehouse in the local town has offered me space in there to store all my extra stuff I can't store in my 6m x 6m house.
See my cabin in the woods signature below if you want to have a read of what I've done up to December last year. Yes I know I NEED to update the blog, sorry.
I tend to agree with you Rik, I think that it's possible for multiple people to share land, resources etc and be a part of the experience but I doubt that it's possible to have the complete experience. When it comes to multiple people contributing to land, or an island etc then they would basically have to give the money to some sort of trust that's got rules and abide by those rules for ever more.
If we ever collected money for woodland or some such it would be governed by rules we'd all have to abide by so everyone would have to go into it very aware, I do dream sometimes though of having small woodlands all over the UK so that our members can use them as a place to escape to, practice skills etc, they'd still need to be managed and all that but it would be brilliant for everyone to have somewhere they can go.
A "homestead" would normally be considered as a single family. That gives the freedom and a measure of independence that most people seem to be seeking when they consider homesteading as such.
A "group buy" would certainly be possible but it would change the dynamic in the way you and Rik have suggested. Rather that an independent lifestyle, you'd actually just be creating a new village in and of itself (albeit themed to a common interest) A colony or commune by another name.