I really don't get the leaving present thing. Someone who does your job is leaving to get paid more money and so the people who are on less money should put their hands in their pockets and give the person who is going to be better off a present?
I normally jiggle the envelope, rummage in my pocket, jiggle again, write my name on the front and pass it on. I'm not a complete bastard, don't mind retirements, redundancies or even babies as long as I know the person, but coughing up for "Terry from HR" that you have never met who is going to be a HR manager for big company is a bit of a mickey take for me.
One bloke at my current place was quite unpopular, he was, in fact, a complete arsehole who'd kissed arse and became a departmental manager and had made the whole places lives a misery to feather his own nest by introducing silly targets and instigating random sackings to keep people on their toes.
When he left for bigger and better things one of the middle managers quite fancied sitting on his coat tails, so sent round the envelope to 300 people. To get the ball started they'd chucked in a tenner and a handful of loose change.
When it came back it had 43p in it, washers, foreign coins and an assortment of paper clips, the middle managers had to have a whip round and we all had to stand there while they presented him with about £100 worth of whisky and cards and listen to his self promoting, gloating speech.