This thread has given me a lot of food for thought. I have already used my backhoe hydraulics to pull a log to me. (Hurricane Irene cleanup). Based on the advice I have read here, I would not even try to "tow" a log by driving the tractor, with a chain attached to the movable parts of the backhoe.
I have looked my JD 48 backhoe over for a good place to attach a chain to the frame, that would not come in contact with the stabilizers or the hoe mechanism. The rear portion of the "footrests" are about 1/4" plate that are welded to, and part of, the frame. There is an angle on these, where my chain's grab hook would fit. In a pinch, and if the log is not super heavy, I may hook there.
I also have an idea for something better. Tractor Supply's web site shows an 11,000 lb bolt-on D-shaped "anchor ring." Unfortunately, the web site did not give dimensions. I'll have to see if I can find them in the store, to check the size, and particularly the bolt spacing. If I'm real lucky, the bolt spacing would be the same, or close enough, to the spacing of the pairs of bolts that go through the backhoe frame. This location would not interfere with the operation of the backhoe, and would provide a convenient and strong place to attach a chain. If this works out, I can make a chain "bridle" that would hook to these anchor rings on both sides. The effect would be similar to how you rig a waterski tow rope, to avoid the outboard motor. In this case, the bridle would provide a means to pull from the center, but avoid the backhoe in the middle. If I implement this idea, I'll post photos.
I am also working on an idea for log pulling with the backhoe dismounted. Some of the locals in my area use a "trapezoid" on their 3 point hitch that is similar to the Log Hog from Norwood (also available from Northern Tool.) I'm planning to assemble one from a 3PT drawbar, Northern Tool's Drawbar stabilizer, some angle iron, and two grab hooks. It will be a multi-purpose device, which can serve as a receiver hitch, a drawbar, as well as a log pulling device. It may not be quite as rugged as a Log Hog, but it will cost me about $150 less. When I get the pieces of this thing together, I'll make a new thread and post photos.