I'm guessing yes. But would it be in any way feasible to recall an email you may have sent before it'd been opened by the recipitent? Or I'm guessing once it's gone, it's gone, right? I'm being stupid, aren't I?
How good would that be though? The amount of people that would avoid the sack would be pretty substantial, I'd reckon
This thread is inspired by me making a tit of myself at work just now