Buddy of mine has a 100 yard range and permanent bench set up at his house - about 3/4 mile from my house. His bench is okay but it was designed for his height so I have to build things up a bit. We just use homemade sandbags for rests. Very convenient setup for himself and his friends. There has only been one time that I've gone out there when anyone aside from us did any shooting. Sometimes we have to wait for his cattle to get out of the way though.
Another friend and I constructed a portable bench which was made using a basketball backboard I picked up at a yard sale for $2. It a white synthetic material and makes a good table. He keeps it at his house since he only did 90% of the actual work.
We've used it a grand total of twice I think. He got a little carried away with the angled steel and it isn't as portable as either of us had envisioned - really not that bad either.
Whatever sort of table you shoot from... pad your elbows. OUCH!!