Not noted for their technical tips the folks at birdwatching.com posted this quick check for dipvergence (convergence in the vertical plane) by viewing a horizontal wire with the bins a little way from the eyes. The wire should "line up" between both tubes.
http://www.birdwatching.com/optics/.../alignment.html
Seems to work too. One of my old Nighthawks is out of sorts according to this. Everything else seems fine.
Kevin - I know that what you have stated about dipvergence is accurate, but for a few people it isn't. Allow me to explain. For whatever reason, binoculars which are in perfect colimation, to my eyes, never show the horizontal line to be on the same plane. One barrel, the right one, is consistent in showing the line to be lower. I discovered when hand colimating that making the lines coincide actually introduced a serious error in colimation for people with normal eyes. My opthamologist told me that my brain "sees" differently than most people, even when the binoculars are in colimation. Strange as it seems, it is true for me. John