I've been thinking, I have a long garage with no windows, What if I built a false wall at the back, to store all my bikes, and other expensive items, then I could block off the door way with an old door and general large detritus around my garage, so it can't be seen. Might take me a few mins to get my bike out, but would be worth it surely.
Anyone else attempted this.

Sounds like a plan..

You'd end up leaving it there.

why not just rent it out as accommodation/workspace to an anphetimine addicted portugese taxidermist and ask him to keep an eye on your bike?

Inspired by the sheeps head behind the wall post the other week.

I'm planning on doing exactly as suggested. Occurs to me that I won't need to brick all the way up to the roof- thus allowing a bit of air circulation.

I put up a false wall last year, not the secret room version you are describing, but blocked entry from the front. I've no intention of ever putting a car in. There was a side door already so just reinforced that.

I actually recessed the false wall a couple of feet so I could still store the sort of crap you keep but never actually use, old tins of paint etc at the front.