Didn't know where to post this, so I guess this will have to do unless a moderator moves it.

Anyone know of any software that allows you to preview your email campaigns in multiple email clients like gmail, yahoo, aol, etc...? I know of couple of paid ones that include this feature, but I don't want to pay for some mailing service just for one feature. Any ideas?

You probably dont need such a software ! As long as you can make it standard HTML compliant and not use any M$ specific extensions (such as those added by office) your mail will look similar throughout.