I submitted the Alpine Hammock. It's a combination hammock/bivy. Technically the whole kit comes in above 2.5lbs, but if you omit the suspension straps and one of the poles it meets the 2.5lbs requirement (while still being a perfectly functional bivy).
Personally, I like the comfort of a hammock, but sometimes you just don't have anything convenient to hang from. The Alpine Hammock is a great compromise, because it doesn't feel like you're compromising at all.
@EZ_living - Cuben is a great material that has high waterproofness, does not stretch/expand when wet (like sil-nylon), and is quite light. My issue simply is cost - a tent made out of cuben would be cost ~$200 more. So by restricting cuben from this poll, I am eliminating the tents that are too expensive for most of us.
If you could only one own tent, what would it be? Could be single or double wall or tarptent, freestanding or not. But let's assume you don't have unlimited funds, hence the "no cuben fiber" qualifier. Otherwise, these tents would all be $500+. I've been using the TarpTent Contrail for seven years and am wondering what might be a good replacement.