You don't even have to leave the comfort of your cozy home to get extension form 4868 for federal and state tax returns. You can google "tax extension forms" and you will find a number of websites that will allow you to download "pdf" files for you to print and put in the mail before midnight. There are also sites that will let you file your 4868-s online for free.
But be careful! If a site asks you for your social security number and a password before you even register, it very well could be "phishing" for your online identity.