encrypt username/password

 I have  2 sets of username password stored in web.config in plain text.
I don't want them to be seen by others, is there a way to encrypt that?
in the web.config file there is something like this:
<add name="ActivityRegConnectionString" connectionString="Data Source=sql1;Initial Catalog=ActivityReg;User Id=Myuser;Password=mypassword; Pooling=False;Connect Timeout=0; " providerName="System.Data.SqlClient"/>
also I have one user for admin site:
<authentication mode="Forms"> <forms protection="All" timeout="30" loginUrl="AdminLogin.aspx"> <credentials passwordFormat="Clear"> <user name="admin" password ="mypasswords"/> </credentials> </forms> </au ...