I presently just use two rubber hoods, one is a non-collapsible one for my Mamiya, the other is a Hama-style sorta monstrosity that I use on my big ol' 35-105, usually for inclement weather. (It's nicknamed 'the front porch' and is actually pretty imposing. Also, because it's so big around, it's actually kind of a pain to stow in my bags. Rubber hoods just tend to add diameter, which adds up pretty quickly on a bigger thread size. Here, I'll show you.
This is the usual metal one:
(doing bad Crocodile Dundee impression. Lens shade? That's not a lens shade)
And this is the 'Front Porch.' (Now that's a lens shade)
Yeah, it gets people's attention when that rig is pointed at them, but it is pretty nice for walking around.
After posting this, an old idea came to mind, which I had for this big old beast of a telephoto zoom I have (It's a big old Formula 5 75-205 steady 3.5. Scored very cheaply on Ebay on a lark, and as a stopgap, but I came around to really like it. It's so obscure I've named it 'Googleproof,' though, if anyone knows about these. Anyway, the salient point being, it's so large, and has only a screw thread on the front, I had been about to resort to an odd plan to get necessary hoodage on there (Another solution came along, so I didn't actually try this, but here it is
Basically, the idea was that I could get a pretty straight metal hood on Ebay, and I was going to get one of these, disregarding the thread size, but rather so it'd be just big enough to put reversed over the front of the lens with a bit of camera back foam or tape stuck inside to prevent scratching and rattling when so stored: then attach it with a step ring to make it fit up, thus basically having a custom hood.