Everyone has there own opinion of what works, but for me, I like crushed asphalt the best. Essentially, it is the stuff that they grind off the roads before they resurface them with a new layer of asphalt, except it is crushed further to make it more uniform and get rid of any potentially large chunks.
It is a little hard to get it seems, until I found a local hauler who uses it regularly. It is somewhat like #53 limestone, in that it packs very well (even better then most limestone), but I like it much better then the #53 because it doesn't have the fines so it drains much better. Also you don't get puddles as quickly and especially you don't get the slop from the fines when it rains which get tracked everywhere.
I think it looks good, in that it is fairly black after it down and has rained on it, but some people prefer the crisp, clean look of a white limestone driveway. But this stuff packs so well, even plowing snow doesn't move a great deal of it around if you use some reasonable care, unlike most limestones which always seem to get pushed into the yard or ditch, unless there is nothing loose on top anymore.