I am absolutely nuts about the Black Diamond Firstlight for lightweight touring & hiking use. I just used it for a (very rainy) 15 day tour through Japan in April and it performed perfectly in adverse conditions (heavy rains most nights, temperatures close to freezing on some nights).
It's a single-wall silnylon 1 or 2-person tent. It's about 6'x3'. I'm 6' tall and can sleep comfortably in it, stretch out, move around, change clothes, pack gear, sit up, etc. The walls are steep and tall so there's lots of headroom for the size of the footprint. In 1-person mode I was able to sleep in it with all of my gear inside the tent (4 ortlieb panniers, a handlebar bag, and a fully stuffed/extended Carradice camper longflap) and still have enough room to stretch out. In 2-person mode (with my girlfriend) we were able to sleep w/ room left over for personal items (clothing, jackets, shoes, toiletries, non-waterproof bags, etc.) while the waterproof panniers stayed outside the tent. Even with two people we have always slept comfortably in it.
Here's a link to what looks like the tent on sale for $239. MSRP is $299 but you can often find it for closer to $230 online. (I got mine for $230 on Ebay).
http://www.basegear.com/black-diamon...ight-tent.html
The tent weighs 3 lbs. It's absurdly small and light when packed up. Close to the size of a Nalgene bottle. It's also a lovely goldenrod yellow that gives a delightful cast to morning light... makes you happy to wake up in it
You have to seam-seal it yourself, but I have had no problems with leaking, even in nonstop 12-hour ice-cold downpours. I once woke up with 3 inches of water underneath the floor of the tent... I had pitched the tent in a depression and a heavy rain started after I fell asleep... woke up essentially floating on a small lake

Not a drop came through the floor.
This tent has received awards from Backpacker Magazine, etc. Can't recommend it enough!
Note: This is of the smallest-size and cheapest Black Diamond single-wall tents. There are larger sizes as well, always astonishingly light for the size of the tent you get.
Tx,
Sam