Sleeping Pads
It's a tough decision as to what to sleep on. Should you use a hammock, closed cell foam pad, or inflatable pad? It really depends on your comfort needs and weight expectations. Let's go over a few options.
Closed Cell Foam Pads
Closed cell foam pads are my pick. They are affordable, light weight, and extremely durable. You can use them to sit on when breaking or slap out on the ground to sleep. They are insulating for 3 season camping. Comfort can be an issue for people. If you are a side sleeper, you may not find it very appealing. I can sleep any way and don't mind harder surfaces so this is a good solution for me. The other concern is size. They do not pack down as small as other options. If you have a frameless pack, you might find this helpful. You can put it in to help give support. If you have a frame already, you will probably hang it off the back or side of your pack. For the thrifty, it is affordable and will last for years. This makes it a great choice. Below is the pad I am using.
Hammocks
Hammocks are comfortable and pretty light weight. However, you have to remember you will probably need something under it in cold weather and mosquito ridden locations. You will also need a tarp to go over it in wet locations or on very windy days. A mosquito net is mandatory for me! All of these things add weight though. You also need to have a location to hang it. If there are no trees or poles to utilize, it becomes a ground covering for tarp camping. The comfort is lost. Here is a hammock set up that includes most of what you need. You will still want an under quilt at times and always sleep with something thicker under you so you can't be bitten by mosquitoes from below. The weight may seem high, but remember, you have have the tarp, hammock, netting, and setup components so it's not really bad. You will probably want to replace the stakes for something lighter eventually though.
Inflatable Sleeping Pads
Inflatable sleeping pads are light weight, very comfortable, can have high insulation properties, and pack down small. The size and weight or packing make these very appealing to me. The price is a bit higher and durability can be in question, depending on locations. The problem I have is punctures. In rough environments, I don't want to end up on the ground because of a leaking pad. You have to decide what is more important, durability or comfort and size. It is a good option, just be prepared. Below is an inflatable pad that weights only 14.5oz and comes at a very reasonable price.