I have used a program called emailSTRIPPER from PaperCut software for years. It's great! It is only one EXE file, so it works great as a portable program. I thought I'd mention it so that maybe someone will package it for PortableApps.com. Here is some info about it:
Copied from http://www.papercut.biz/emailStripper.htm
emailStripper is a free program for cleaning the ">" and other formatting characters out of your emails. It will restore "forwarded" or "replied" emails back to their original state so they're easier to read.
Actually, there are a couple Thunderbird extensions for doing that.
Sometimes, the impossible can become possible, if you're awesome!
I've been looking all over for a way to add the mark [INITIALS]at every comment I make in the original msg, but found no way.
It's a standalone app, you can find it here: http://www.dsoft.com.tr/stripmail/
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Teen1: Oh, here comes that cannonball guy. He's cool.
Teen2: Are you being sarcastic, dude?
Teen1: I don't even know anymore.
"In three words I can sum up everything I've learned about life: it goes on." -- Robert Frost
"In three words I can sum up everything I've learned about life: baby ain't mine." -- Adam Holguin