As others have mentioned the online Navionics charts are cool to work with.
Navionics ChartViewer but my favorite thing to do is to use the Navionics app on an iPad. I can get comfy on the couch, plan routes, save to my account, share with my friends, family, etc. You can't share the routes from the website but you can share from the app (ipad, iphone, tablets, android phones, etc).