Being one for detail I'm amazed every time I receive emails from different users from the same organisation but with differing signatures.  Most of these emails come from small to medium businesses with some really slick marketing in general, in fact one could relate it to somebody wearing a very sharp evening suit with a pair of white sport socks! 

Microsoft seem to have omitted this essential feature which has prompted a host of third party applications available in the market place.  My preference is a product from Exclaimer called Mail utilities for Exchange that simply requires installation on your exchange server.  Not only can it standardise the signatures across your organisation but individual groups can be created to alert the recipients of important company information from differing departments as it integrates with the active directory.  A console can also be created for non technical administrative staff in order to manage the signatures, so there's absolutely no need to get dressed in the dark again!