I use "dh" to refer to Ed while posting to message boards. I try to remember to just call him Ed when posting to my LJ but sometimes I slip up.

I've also seen so, dw, dp, and df. Also xh. For kids there's dd and ds, and if you're a blended family there's dsd and dss. And of course there's MIL and FIL and SIL and BIL and X can be appended to any of those, as need be. Or STBX (soon-to-be-ex) or "future" (which usually seems to be typed out, rather than abbreviated to F). Which reminds me, I have on a few occasions seen FH when someone is really fed up.