Lots of hammock stands out there. Here's my version.

Some general comments:

The metal pipe is a critical component as it keeps the stands from collapsing in towards each other. You could use most a any rigid pole but it needs to be about 13 feet from end to end to get anything resembling a normal hang. I used 1.25 inch thinwall galvanized pipe like you use in chain link fencing. I got two sections and then cut them down because the sections are sized on the ends to fit inside each other.

I used 6" hinges with one long side and one rectangular side as shown in the photos.

Some people suspend the pipe using Amsteel loops or whatever. I used chain and S hooks which makes it easy to adjust the height of the pole from the ground.

For legs I used 2" x 2" x 6.5 feet long.

The tripods collapse down to 6.5 feet long, and the 13 foot metal pipe comes apart into 6.5 foot sections also.

You need something near the bottom of the legs to keep them from spreading on smooth surfaces. I used simple eye hooks and paracord.

I use these stands all the time when I get back from camping so I can hang my hammock, tarp etc in my basement to dry/air out before stowing. It's also very useful for test fitting stuff to your rigs before going outside.

Just another take on these

http://www.youtube.com/watch?v=lHUVS2g-n04