Helmet Technology...

1991 Upper Deck Football - #372 - Steve Deberg

...sure has come a long way since the early '90s.  I think the "enclosing the top" part of the helmet was the greatest stride.  Maybe the "replacing the visor with a facemask" was pretty important, too. 

I can just picture Reggie White coming through the line and clobbering DeBerg's visored head right to the turf.