Plus! doesn't do password-protection of folders... it actually encrypts each individual file. In other words, it changes the original file and replaces it with an encrypted version, and the only way to decrypt it is by using MsgPlus. I think that's quite a difference from "password protection for folders"
As for encryption programs, the one linked to from that PC World article looks good (
http://axcrypt.sourceforge.net/) and it's free. More free ones can be found at
http://www.snapfiles.com/Freeware/security/fwencrypt.html.
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