Not sure if this is what you're looking for, but try this link:
ConvertToSecureString Class[^] on MSDN.
It has some examples there. Edited: This can't be the right answer :)
On second thought look at the comments at the bottom
here[
^]
Maybe that's where this mysterious method came from ;)
private SecureString ConvertToSecureString(string value)
{
SecureString ret = new SecureString();
foreach (char c in value)
{
ret.AppendChar(c);
}
ret.MakeReadOnly();
return ret;
}