I used to live on S.I. and work in downtown Manhattan and every day on my way home from work a confused tourist would ask me why I was on the boat and where it was going. The Staten Island Ferry is a commuter boat, when it gets to the other side they will force you to get off and you’ll be in Staten Island, which, lets face it, is really not somewhere you want to be when you should be looking at all the fun touristy stuff in Manhattan. If you’re looking for a free view of the Statue of Liberty (no, it won’t actually take you there, but you can see it) or really like gardens (Snug Harbor is in walking distance from the ferry and has beautiful gardens) take the S.I. ferry. Otherwise don’t. Its a waste of 40 minutes of your life.