It's nearing the end of the vacation year for me (June 1st to May 31st).
My employer has a "Use it or lose it" policy when it comes to accumulated vacation time. I can roll over up to five days, but anything over that is forfeited if not used by the end of the year. Vacation days cannot be turned in for cash value, true for both salaried and hourly employees. Their reasoning is always "We want you to take time off" but I'm pretty sure it's really "We don't want to pay you more".
Being the lifeless single man I am, I never really think about time off until the end of the year then I have to quickly fit as many days as I can without leaving my projects and coworkers high and dry. This usually takes the form of me taking off every Friday for a few months. I'm sitting on 20 vacation days right now. And am going to be using 12 of them up to take off every Friday between now and the week of memorial day (Good Friday is already a day off). That leaves me with 8 days left. Probably going to ask for the week of memorial day off too, which will bring me down to 4 days to roll over.
Work is just such an ingrained thing in my schedule, I don't really ever think about ever NOT working. Projects that are multiple months long lead to time flying by. I mention to a coworker back in August that I need to make sure to use up my vacation time before the end of the year, and suddenly I wake up one day and it's the end of February.