Happened to a friend of mine while he was on his honeymoon. Through a slip by management people knew it was coming. He wanted to know before he left, but they wouldn't tell him. So he ended up checking his voicemail everyday while he was on his final vacation.
I've had it happen too. Granted, it was kind of a bullshit zeroth job where it happened and the company folded a month later, but it still sucked. I almost brought in cupcakes to share with the company...
For me, this was a real eye-opener.
It would not have been a big deal for HR to wait another day, and then lay him off.
Another employee, also laid off, 2 days after moving out of his aunt's house and had put a deposit down on an apartment and DSL connection.
I think I left a month later right before the company imploded.