Email Stripper 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.
Bounce spam. Throw back undesirable e-mail to the sender with a faked "bounce" message. Mailwasher does this and much more - see the details under Security. But if you do not want all the facilities of Mailwasher, this is a neat program.