I have been challenged with finding a way to access a POP3 mailbox, pull down a message with an attachment, then forward it to another email address after manipulating the subject line. I have been doing some digging on the internet and I have not found anything the looks viable so I thought I would toss it out here to see if anyone has done something similar and can point me in the right direction.
I don't personally know of a ready made solution, but you might have more luck if you look for a .NET library that can do it. You should be able to use Add-Path to load the library in PowerShell, then you can use the classes and methods in the library directly from a script (or interactively from the terminal). I'd look for C# sample code, as it's easier to adapt it to PowerShell code.