Microsoft Exchange Server team has created email signatures for people on the Exchange team to advertise career site, but due to geeky email-related humor in them, it can be used by anyone. Clicking on signatures will take you to download locations for that specific signature.
How to install them into Outlook:
1. Unzip the signature and copy the content of signature ZIP file to your Signatures folder.
By default on Vista: C:\Users\<Alias>\AppData\Roaming\Microsoft\Signatures
By default on XP: C:\Documents and settings\<Alias>\Application Data\Microsoft\Signatures
2. In Outlook go to Tools > Options > Mail Format > Signatures and choose the signature for New messages/Replies. Alternatively, you can insert a signature to just some messages if you go to the Insert tab and choose Signature in Outlook 2007.
Source:→ Exchange Team Blog
Microsoft, Exchange Server, Email, Signature, Outlook