When cruising, I connect through a cell phone, at about 9600 baud. This was new a couple of years ago, but now probably 50% of cruising boaters who stay in the US use the same approach.
The alternate is to carry your laptop to a marina phone line, or go to the local library; almost all libraries these days offer internet connections, usually limited to 30 minutes or so.
I also manage to visit friends and family with high speed connections when I get a chance!
Those with lots of extra $$$ use satellite phones at higher speed, but those folks are mostly either still working, unusually affluent, or (in at least one case we know) retirees from the satellite phone company who got service as a retirement benefit.