My favorite tent is the Sierra Designs Clip Flashlight CD.  It fit's one person and a dog very comfortably.  They make them to fit more though.  Here's a few questions that would help pin point down a good tent for you.  Do you want a free standing tent or non-free standing (what type of ground surface will you primarily be sleeping on)?  3 season or 4 season (will you be snow camping)?  How many people will be sleeping in it?  How often will you be using it?  What is your price range?   

basically i am good with either freestanding or not. i am looking at the marmot home alone bivy.  only thing i will be using it for is kayaking overnighters and maybe the occasional backpacking trip. was going to go with the nemo gogo le but the place i was going to get it at sold out and is no longer offering them. i want something for 1 person that is light and packs small. would like to keep it under 200 if possible.

Hey,

     After owning bivy sacks for some time, I finally got rid of mine. Without poles to hold the fabric up off of you, a bivy sack will get you wet from condensation. They are best for survival bivy sleeping above treeline and in the alpine environment. They are best when it's well below freezing.

     I think for ultralight camping the tarp/groundcloth setup is the way to go. I'm not experienced in it, but have been around others doing it. The guys under the tarp were always way more sheltered protected and dry than the bivy folks. And, you can have a tarp system that weighs less than a gore tex bivy. With a tarp, you can get yourself and all of your gear out of the rain. With a bivy, everything inevitably gets wet if it's rainy. If you get a fancy bivy with poles and so forth, you approach or equal the weight of the lightest real tents out there. I'd say either get the lightest tent on the market, or get a tarp. Not a bivy sack.

     The only reason not to tarp it would be for wind protection and insect protection. Otherwise, the tarp system looks awesome. I guess one has to get over wanting the cosy feeling of being zipped up in a tent too. Mice can crawl over your head in the night without things being zipped up. Anyway, those are my thoughts.

     Have fun...

thanks for all the tips. i have it boiled down to 2 so far.

http://www.backcountry.com/marmot-home-alone-bivy

http://www.backcountry.com/the-north-face-tadpole-23-bx-tent-2-person-3-season

the bivy is small and lightweight.  it also has poles to told it up off of my sleeping bag.  The tent is a little bigger but can be separated and spread out in the back of my boat and i can get it from rei for a lifetime warranty.

A friend of mine has that North Face tent and brings it on boating trips. It kicks ass, and packs down extremely small. One flaw is there's a flat spot in the middle of the fly, and if you don't seal the seams running through there carefully you can get leaks.

Bivies, on the other hand, pretty much suck.

http://www.backcountry.com/msr-hubba-tent-1-person-3-season Half the weight for a not much more than the TNF tadpole. Bet you could find it online cheaper somewhere, and you can set it up with just the fly and footprint or the whole thing.

Agree with warlick. If you use a bivy, make sure you put on dry base layers ( that is where a good portion of moisture comes from) and get some ventilation going. That being said, my set up of choice is the ultra light tarp and bivy combo...tried and true in many rain storms.

i like the msr hubba tent that ellingferd recommended.  its small, compact, lightweight, and freestanding. soon as i get paid on the first, gonna get it from rei. thanks for all the tips and help on this topic. hopefully we still get to do the green trip next month so i can try it out.