Hey all.

From the great reviews from this forum, I bought one of these $35 cases for my HD500 from here: http://www.rondomusic.com/pdc410d.html

The HD500 fits perfectly in it and there's just enough clearance at the back so that cables can be plugged in without having to remove the unit from the case.  The only problem was how to properly secure the HD500 to the case so that it doesn't bounce around in travel.  Of course, you could pack more foam into it to hold things in place, but I thought it'd be great to have a bit of extra storage space on top of the HD500 for a cable or 2.

The velcro that comes with the case is pretty much useless because the HD500 has rubber feet which prevent the velcro from having contact with the fuzzy part of the case so I ended unscrewing the rubber feet from the HD500 and replacing the screws with longer ones.  This allowed me to mount the feet on the outside of the case, pass the screws right through the case wall and fasten the HD500 to it.  The rubber feet on the outside help prevent the case+HD500 from sliding around.

Here are some pics

I used 1" screws for the back and 3/4" screws for the front to angle the HD500 forward a little.  This gives even more clearance for cables plugged into the back.  Note I also used 4 rubber washers in the back and only 2 up front.  The washers I found were 1/2 the thickness of the HD500's rubber feet.  I only replaced the screws/feet on the corners of the unit.  If you want, you can replace the 2 middle screws as well.  I just didn't want more black rubber feet sticking out the side of my case

Here's what the feet look like.  I took the bottom plate off the HD500 and used it as a drilling template for where to put the holes.

The HD500 It's perfectly in this case with about 1/4" clearance on the sides and about 2" in the back

Here you can see a fairly long 1/4" cable plugged into the back and it just clears the lip of the case.

I used 4 screws, 12 rubber washers and 4 metal washers for this little project.

I'm really happy with the case.  It's amazing value for $35.  It's about as tough as your average instrument case but not as tough as a true flight case.  The walls appear to be 1/4" particle board covered with thin aluminum layer.  Now I don't have to shove my HD500 into a backpack anymore!

Enjoy!