Yes these are also known as Tower Forms. Anucha posted a wonderful display of different trees. Many species have more of a tendency to grow this way which makes them more useable.

Rick

Here's my one attempt at doing this tower form at it's current progress. I'm using what I believe to be arabicum bouquet. Oh, sorry for the blurry pic. Took the picture early this morning while fending off mosquitoes.

Kirk

I love it! I didn't know you can do this. I have a question for you experts. I didn't know much about adeniums when I inherited this one so I put it in a tall pot. Now I have "carroted" roots that are very long. Is there anyting that I can do about this? Can I lift a potion of the roots to be exposed and repot it in a shallower pot? This all depends of course if I can save the plant at all. So far a few of the branches have new green coming out, Here is a link to my plant....
http://forums.gardenweb.com/discussions/3277304/im-so-upset-pray-to-adenium-gods-for-me?n=14