Personally I use a table, I have seen others build a cradle from two plywood uprights with hull shaped grooves fastened to a board or even PVC/abs pipe to form a cradle.
Designing a boat stand depends heavily on what you need it for. Stands range in purpose from preventing under-hanging props and rudders from banging on the table to protecting the ship during transport to being a complete travel kit with all necessary support gear/tools in one spot.
Something heavy on either side. I usually toss a block of wood under the aft end of my derf to keep the running gear off the bench, but otherwise its stable enough without a cradle. Nylon straps slung from uprights make a decent and adaptable cradle.
If my ship doesn't have a big flat area on the bottom (or even quasi-flat), I get a flat board, and use super glue to attach wood blocks against the hull at front and rear to keep it from rolling while I work.
Just a flat workbench for the most part. I will use an old SLAs placed strategically inside if I need to keep a ship over on it's side while I work on it. I've also got a few foam blocks from various packages that can be used to help prop them up as well if the hull likes to rock.
I have a 4'x8' assembly table with my table saw inset so I have lots of feed out. I was thinking of using my cornhole bags to help prop it up since its not nice enough to play right now!
