I'm trying to find imput on what sheltering-items I should include in a hiking-kit.
Currently I use a Coghlan's heavy-duty space blanket as the 'roof' and a poncho as a groundsheet, while sleeping in a Coghlan's orange survival-bag (soon to be replaced by a heatsheet-bivvy).

I've also been thinking about using a small hammock.

So, what's your shelter set-up??

US Military bivvy bag.

I use a silnylon tarp, a hammock, and closed-cell foam pads. You'd think the hammock would reduce the need for gear, but what it might save (groundsheet) is offset by the needs it introduces (foam pads for keeping your backside warm).

So the weight comes out about the same as for a tent. But I still like the novelty and flexibility hammocks afford. Also, for an older fellow like myself, it gets you up off the ground, providing as it does a chair-height shelf as well as a chair and bed.

I'm talking about a Mosquito Hammock, i.e. one with a built-in mosquito net. Otherwise, you'd have to think about carrying netting in addition to an open hammock.

http://www.mosquitohammock.com/

It's my goal to include a less expensive polyester tarp (at least 8 x 10 ft.), precut paracord tie-downs, aluminum pegs, a bivy sack, and a closed-cell pad in all my vehicle kits. That's my notion of adequate shelter for my environs (Florida).

Bear

Hammocks are good, particularly in the rain or if you have lots of ants around. But they aren't really suited to cooler weather.

My shelter set up depends on what I'm carrying, but in warmer weather I either do a hammock under a tarp, or a brush wickup. In cool weather, I add more insulation. In cold weather (sorry, Jim, from what you've said about your climate, I'd pretty much stick to warm and cool weather configurations) snow trenches and caves, and variations there of.

Being in South Lousy-anna (where the mosquitoes run rampant & large), I use a tent, foam pad, lt sleeping bag (used as additional cushioning in spring, summer, & fall), cover w/a falsa blanket, pillow, and mosquito repellant.
My BOB has a Army poncho, 55gal polypropylene bag, pillow, falsa blanket, & mosquito repellant. I am quite proficient in constructing brush shelters (lean to's, Apache Wickiups, etc) & rely on those skills primarily when the need arises. I stay in practice by teaching my nephews those skills when we are on camping trips.

I have various setups for shelter in my different kits. From very light to comprehensive.

My PSK has a AMK Heatsheet and some type-I paracord for shelter, for the winter (in central AZ) I add a 60 gallon clear plastic bag.

In my hiking and SAR kit I have two 60 gallon trash bags, two AMK Heatsheets and a Heatsheet Bivy.

For winter and backpacking trips my kit includes a Mountain Hardwear bivy sack and an Oware silicone nylon tarp. I usually travel with treking poles, which make great tent poles. Even when not expecting to spend the night, I always add a foam pad and a heavy duty space blanket to my kit for winter trips where snow is a possibility. It isn't the lightest setup but it works very well.

Being a fan of bugging in as opposed to out, we don't have a BOB per se. What we do worry about is being stranded on the road, or while on a walk/hike. So in our vehicle we have a 7x7 three season dome tent, mating mummy bags (20 and zero degree), camprest self inflating pads (the thick ones, as we get older we like our creature comforts). In my day pack, carried on all foot trips out of sight of the vehicle, is a 10x10 nylon tarp with a jillion tie tapes, precut paracord, and aluminum gutter nails for stakes. Also a Thermo-lite Emergency Bivy Sack (the two person size). In anything near rain season lightweight rain gear for both of us, the rest of the year at least two 30 gal trash bags. I used to have some nice heavyweight orange ones, but they got too old, so now they are the less than desirable black ones...

That depends on my trip, my short hike setup would be a silnylon tarp, a couple oversized plastic bags and "TYVEK" ground sheet. Would this be suitable for cold winter "NO" I would have to find some insulation layer between me and the ground like leaves etc. If I am unsure of leaves in the area, I have a self-inflating pad full length that packs down pretty small.

On longer trips, I bring a larger tarp and fashion it into a "Wedge" shape structure or a backpackers tent.

A North Face 2-man tent with a ground cloth rides in the car trunk. It's a bit heavy to carry around.

Also have a heavy green tarp in the trunk.

For carry, I have an 8X10 SilTarp and I always have one or two "space blankets" on me somewhere.

My small kit has a 10x10 silnylon tarp, a 6x8 silnylon tarp, a Thermo-Lite 2.0 Bivouac Sac, for cold weather I add a 2 pound over-bag. This type of shelter setup served me well on SAR missions, and I was comfortable on a number of unplanned overnights.
My large kit has a 2 man tent, 0 degreeF sleeping bag, and thermarest pad.