Wolfie,
When I saw the thread title, I thought you were looking for a way to stop threads on this site from spinning off into irrelevant fancies. As if!
It might help if you told us more specifically what you are trying to make. For hex head bolts, your washers idea is on the right lines, though working out the thickness of the washer needed (from thread pitch and angle change needed) and making one washer to suit would be much better. If it's more complex, like two machined parts which need to screw together, you may be able to come at it from behind, as it were. Make the machined surface of the female side, but leave the rest unmachined; drill and tap, try male part in it, shave off bits of female surface until angle is right, then machine rest of female part to suit. Bit fiddly, but it that's why I say it helps to know what you are making.
If it's purely cosmetic, as is often the case in model making, use a dummy bolt (unthreaded) and Loctite in place, then you can orient it how you like.
David
Edited By David Littlewood on 11/07/2012 12:07:39