I think an e-mail is cool. At my job, the worst thing I see is they let people drive 1-2 hrs to work, sign on, work about an hour....then have a meeting just to say "YOU'RE FIRED!"
Send me an e-mail so I can sleep in, save my gas, and not have to try and stay saved cuz you done fired me knowing I was just 'bout to buy that new Fantasia CD.