Honestly, I don't use support for my camera enough, but when I do, I'm always happy with the results. There's no faster way to negate a great lens and body than by moving them around when you're shooting.
I have four support systems depending on what I'm doing.
My main support is a Bogen 3021 tripod with Giotto MH-1000 ballhead. This is a nice tripod with good height; I can raise it up high enough to get some unique perspectives. However, it's too heavy and long for me normally to carry a lot, so I don't use it often; I've been lusting over a newer carbon fiber tripod for some time and will finally bite the bullet someday. (Note, the updated version of the 3021 looks like has a shorter closed length which would be attractive to me, but it's still heavy at 5.1 lbs.) I switched from a tilt-pan-zoom head to the ballhead a while back. It's a lot easier to use in most cases.
More often, I use my Bogen 3016 monopod. (This is no longer available. I think the Manfrotto/Bogen 679 is the closest currently available version.) I've added a Bogen 3232 tilt head so I can flop my camera into portrait mode. I've made it easier to carry the monopod by adding a Giles Tactical Sling; this is actually a rifle sling that happens to be perfectly suited and cut to carry the monopod. Super convenient.
On top of both of these, I use a quick release clamp from Really Right Stuff with the matching plates for my cameras and lenses. These guys make beautifully milled clamps and custom plates for each camera body. They're a joy to use and totally rock solid. Their site is also fun to read; they have thought a lot about how to build the right gear for shooters. You have to have quick-release plates if you shoot a lot; turning the little screw knob to attach and detach your gear will give you RSI and drive you nuts.
I always have a Manfrotto 3007 Tabletop tripod in my bag. This is a little "pocket" tripod, but it's no cheap plastic support. This is a well-machined metal guy with a ballhead and an extender to give it more height. Super versatile. I've even used it to steady (not hold!) my big 70-200 2.8. It packs up pretty small and comes with its own case.
Finally, I have a cheap plastic Velbon video tripod that I got for free with my video camera. It's a piece of crap, but it's light and folds up small enough it fit in my rollaboard suitcase. It's a good reminder that having high quality gear that is too big or heavy to use is useless.
So, some closing thoughts on supports. It's nice to have a tripod that puts the camera at your eye level while you're standing up. It's actually been useful to have one that goes even higher so I can project a camera over the crowd or a fence (I have to stand on something to see through the camera then.) However, this is somewhat antithetical to having a tripod that is small enough to carry. So, either get two, resign yourself to carrying the big one, or live with the trade-off. I'll probably get two.
Also, if you're shooting with a tripod, it's nice to use a remote release. I love shooting this way. It allows me to be more interactive with the subject. I've also used the remote release when the tripod is too high for me to see through or when I'm sticking the camera out somewhere with the monopod. Finally, it keeps the camera from moving at all on the tripod.
Previous "What's in my camera bag" posts:
Keep it clean