Is there such a thing as a convertable hammock

I don't know of any that can double as a tent but there are several which can be pitched as a bivy of sorts for use under a tarp.

Grand Trunk ATHH: (all terrain hybrid hammock) doubles as a tarp on the ground. http://www.thetravelhammock.com/products/at_hybrid.htm

you can also pitch most hammocks like a netted bivy with hiking poles. you'll need extra guylines is all. the Hennessy line makes this difficult, unless using their new Deep Jungle style (zippered top entry).

Eureka (johnson wax) is making a tent/hammock but i dont know of anyone that is using it, possibly because of its 5LB WEIGHT!!
http://www.eurekatent.com/p-165-chrysalis-hammock-system.aspx

I’ve been looking at hammocks myself lately, since I’ll soon be backpacking in more forested areas, and the Jacks R Better Bear Mountain Bridge hammock does offer a ground pitch option with trekking poles that makes it something to consider.

Troy,

I have never had to use my Hennessy Hammock on the ground, but I did practice with it in the yard. It would make a useable bug bivy under the tarp. What you don't see in the pictures is a ground sheet which it would need since most hammocks use breathable fabric.

-Mark