Are there smart Outlook signatures that can choose to be displayed as an image or plain text depending on the receiver?
No. Once the email leaves your client, you don’t know if that person is going to read it with a web-based client (gmail, hotmail), a desktop client (thunderbird, outlook) or a command-line client (pine, mutt). If you feel that the people you interact absolutely have to see your super-cool image with your info in it, then post that image online and send them a the address. Frankly, putting your contact info in an image makes it far less useful. (I want to copy your address and paste into google maps? Oh, can’t copy text from an image – guess I’ll type it all out by hand…