Cabot: I don't see why the nail knot would not work. However, have you ever tried tying the Surgeons knot, it is a pretty easy knot, even for someone like me that doesn't have very good eyesight. All that is involved is taking about 6-8 inches of both ends and laying then together and then all you do is tie an overhand knot and then do it again.
Check this out: Surgeon's Knot
Or check out this site, it has animated knots where you can see the tying multiple times: Grog's Fishing Knots Index