MacGregorSailors.com

Many of you likely know about this, but I just stumbled upon it.
NOAA offers navigation charts for free. Since it's from a government entity, I'm sure it's legal, free from copyright infringement. This is particularly useful, if like me, you want to trailer the boat to many different locations and you don't want to buy a new expensive chart every time. If you have access to a large format and a laminator, you can save a lot of money. Alternately, you could pull up the PDF on a large tablet.

http://www.charts.noaa.gov/InteractiveC ... ?rnc=11416

They're also compatible with Maptech computer software, including real-time position indication using an inexpensive USB antenna, and all the good stuff that you can do with that (like tracking). I would imagine other software uses the NOAA charts, too. They're the real thing - just electronic versions of what you get when buying printed charts, down to the last pixel.

You may also find these useful: http://xpda.com/nauticalcharts/ A Sailnet member got frustrated that he could not print the noaa charts so he converted ALL of them to .png format and made them available to the public. They are all current and up to date.