There are some sailing video podcasts on iTunes that you can get for free, but the selection is limited. And a lot of the good stuff there is just a preview so you go to a web site to get more. Obviously, video sharing sites like YouTube and MetaCafe have a HUGE selection of sailing content, but you end up wading through too many cell phone videos to find a really good one to watch - but there are some really good videos there. Just have to find them. There are sailing videos in the lower right corner of the SailNet Forums home page, too.
Even though some of these sailing web sites require registering/passwords, here are some sites I know of that have a decent selection of FREE streaming or downloadable sailing content:
http://www.t2p.tv (US based racing and regattas, plus other stuff)
http://www.thesailingchannel.com (from Annapolis, variety)
http://www.cruisingworld.com (Variety plus home movies)
http://www.sail.tv (from England, mostly racing content)
http://www.latsandatts.tv (full TV episodes and other stuff)
(Full disclosure: Yes, Lats & Atts TV is our web site, but it's free for anyone to watch, no registering required, and you don't have to buy anything - so I figured it was OK to include.)
And I'll echo what sailboy said, in that there are quite a few people out there documenting their sailing adventures. As you would expect, some are polished productions, and others are fairly amatuerish. Even so, the "non-professional" videos are still entertaining and quite often educational to one degree or another. I like supporting their endeavors so I can see more.
Bottom line, there is a ton of free sailing video out there if you have the time to find it. Not quite as easy as buying or renting a professionally produced full-length DVD and have it delivered to your door/slip to watch on a TV. But, as they say, "It's all good..."