New Addon: WhisperRelay - v1.0
Inspired by Falkor's "SilentWhisper -v0.1.1"

Update: WhisperRelay has been updated.
What's new for Version 1.0:
1) You can now set the text that is displayed before the name of the person who sent you the text. Previously it was set to "Message from" and that is still the default. But you can now change it to whatever you like via /wr wrtext <Whatever text you like">. Short or long, you decide.

And that's it. The other suggestion regarding "what happens if I get a BUNCH of tells on my alt?" and how to handle that would require me knowing a lot more code than I know at the current time. So, this is version 1.0. I'll keep working on finding a solution for the above but if/when that happens it will be for version 2.

What it does: Relays whispers sent to your alts to your main. Allows your main to reply as alt. Invisible to the original person who whispered your alt.

Example: Joe whispers Alt "Hello"
Alt receives: "[Joe] Whispers: Hello"
Alt relays whisper to your main.
Main receives: "[alt] Whispers: Message from [Joe]: Hello"
Main replies with: "/r What's up?"
Alt recieves: "[Main] Whispers: What's up?"
Alt relays whisper to Joe.
Joe receives: "[alt] Whispers: What's up?"

For the above example just pretend alt and main are your character names.
As you can see it's invisible to Joe... he is having a conversation with Alt. It is also invisible to you as the player in that you don't have to do anything other than you normally would when replying to a whisper.

Installation:
  1. Download WhisperRelay
  2. Unzip
  3. Copy WhisperRelay to your addon directory in WoW. (You must put it in the addon directory of every instance of WoW you are running. Even your main's.)
  4. Enable the Addon and run WoW
Configuration:
Configuration is very easy. Type /whisperrelay (or /wr) for a list of options. There are only two. Turning it off and setting your main. To set your main type "/wr main <name>" (without the quotes and replace <name> with the name of your main character). WhisperRelay remembers the name on each of your characters on a per character basis. This means you can set them main for character A (acount 1) and have it be different from character B (account 1). YOU MUST SET THE MAIN FOR ALL CHARACTERS INCLUDING YOUR MAIN. This means your main will set his main to himself. This is so you don't get an endless loop thing going and crash the world.

Pros of WhisperRelay:
1- Set your main from within game. (No having to manually edit the .lua file).
2- Remembers mains on a per team bassis. (Team A can have a different main than Team B and it remembers that.)

Cons of WhisperRelay:
1- I built it using Ace2 Libs... which means it's bigger than SilentWhipser by a large margin. Especially if you are not running any other Ace2 Mods.


WhisperRelay v1.0

Comments, suggestions, bug reports are all welcome.