Everytime you contact someone, make the most of your signature. Your signature is your online business card - Use it. Everyday millions of emails and online messages are passed backwards and forwards - This is an ideal way of getting free publicity online and sat the end of the day is just a matter of common sense.
It amazes me how many people just don't bother to look at this angle considering it only take a few minutes to set up and will automatically be sent every time you communicate thereon. Online business is all about getting noticed and having your name, email, website or weblog in front of a waiting public and this is an ideal way to do it.
All the main email guys such as Google, Yahoo, MSN/Hotmail etc. have this facility, but why just put your name and website? You can put a little text advertisement alongside this as well, even images that will draw attention each time. If you're not using this free publicity then think about doing it now. It really could make a big difference to the feedback you get, it really is just like leaving an online business card to everyone you communicate to.
Image by *bene* via Flickr