We've got a few home made ones at the yard - 2 tiger traps and a chair - all made with half-rounds, and a trakhener over a natural ditch between 2 fields.
We don't use them much now though tbh, although because they are in the fenceline, some of the horses like to use them when they want to swap fields
We have some tyres hung on a long piece of wood, a tiger trap, some old small square bales with a piece of wood across the top to hold them together a bit more and we made a brush fence by tying bits of fir tree to wood. Oh and an old door to make a bit of a skinny with.
Have fun!
am sure someone posted a while back had made some out of square garden trellis.
We don't have any suitable ditches (they are all huge round here!) so we make a trakehner with rustic poles over a couple of super large black seed trays from the garden centre. (about a fiver each)