If you wear many hats but use gmail to send emails from these many hats, I bet you’ve wished for a way to have different signatures, depending on the context and the recipient.
A-ha! Look in “Labs” and you’ll see a neat trick called “Canned Responses”.
Enable that, save your settings.
Now compose a new email but in the body just type one of the signatures you want. Click the drop down “Canned Responses” (it should be in the same line with “Add CC” and “Attach a file”…) and select “Save >> New canned response”. Give it a name and click OK.
Now after you’ve typed an email that needs that signature, just go to “Canned Responses >> Insert >> signature” and voila.