[zim2323]

Get a gmail account and forward all your accounts there, or use gmail to POP3 them down.

Once you've done this, you can set gmail to reply with the address that email was originally sent to. This is done on the same page in Settings that you use to configure the additional email accounts.

I have 4 email accounts setup in gmail, 3 from hotmail/msn/live, and verizon. They all reply as each address.