Man, you guys are old!  :-)

Commuication and technology advances have to be close to the top for me. 

I remember when, for a good chunk of my life, all long-distance calls were only made in the most dire of circumstances, and they were made from a rotary dial phone, and kept short and to the point.  Now, even 10 year olds it seems are commonly carrying cell phones -- never out of reach.

And mass communication was in the form of am radio or 1 fuzzy television station, both of which broadcasted only from 5 or 6am to 12 midnite, or from a weekly smalltown newspaper.

Lots of labor saving improvements along the way too, but the ability to access information 24-7 (both useful & entertaining) has by far opened up my world the most.