You can make a nice little standard with a 4x4 peice of lumber...about 26 inches long. You can brace it with two peices of 2x4 at the bottom, one piece across and the other at a right angle. These peices need only be about 14 inches long.
Then you can make adjustable heights by taking a piece of 2x4 and cutting it with a 3 inch hole saw and then cut this circle out in two. Actually, I usually cut them in 3, throwing away a little piece so I have shallower cups. This will give you some curved pieces that you screw onto the upright and the pvc pipe will stay in place but roll out if hit (safety feature). Put 2 or 3 of these on your uprights and you can adjust your fence heights.
You can also make little gates (or wings), just like the big guys use, with one of these uprights and a 2x4 frame covered with lattice or pickets and braced at the bottom with just 2 peices of 2x4 placed at right angles on each of the uprights of the gate.
The jump cups can also be used on any other kind of upright to make little 'stone walls' and coups....just look at photos of Hunter fences from full size horse shows...there are a million on the web...and get creative.
If you go to my website www.oldbellfarm.com and click on the 2003 Show Results listed on the left hand side of the page you will see some of my jumps. The jump cups are fairly visable on one of the pictures, so that should help.
Have fun creating.
Eve Dexter