What is the best/easiest way to encrypt a connection string in the app.config file?

MS has a lot of articles on this, but I'm not sure which is the easiest and which is the best etc.

What do you guys use?

The thing is, that we'll be sending a small app out to the users, but we don't want them to be able to abuse the connection string provided in the config file.

Thanks in advance

Edit: And we do not want integrated security, because then we'll have to decide who can access the server and how much etc. We want to use a dedicated SQL server user (not windows user)