There is the "new" CAPICOM Win32SDK redistributable that will let you en/decrypt with the built-in Crypto APIs. It works from within VBScript 5.6 and VFP7.

I like to encrypt myself on the local machine because then I can use SMTP or HTTP or FTP or floppy to pass the file around and be secure that the stuff can't be hacked. Also, my gut says using something like HTTPS on an unencrypted file is slower than encrypting/compressing and using plain HTTP on it - I'll have early next month to test out that theory though.