Last Spring I started an "epiphyte tree" for out on the deck (Lord knows what I'll do over the winter).

The glazed terra cotta planter has four drainage holes, so I covered them with masking tape and stuck pieces of 1/4" polyethylene tubing through them. I drilled two holes horizontally through the base of the driftwood and inserted two very long lag bolts to provide some lateral stability, then after positioning it in the planter, I filled it with quick-set concrete, the kind you pour in dry, then cover with water to seep in and cause it to set. The damned thing weighs about 25-30# now. Once the concrete had set (30-45 minutes), I extracted the PE tubing, so now it has drainage paths through the concrete.

I started with some tillandsias and branching neoregelias on the branches, later adding tolumnias, and more recently I added some mini-vandaceous plants (V. falcata crosses). Here is the "tree" with the the orchids added, about a month ago:

That clump of tolumnias at the base decided to bloom now - it's one of several Tolu. Jairak Flyer cultivars: