While I don't consider time and money to have any sort of simplistic equivalent, those times when I consider money to equate to time aren't about getting a particular service, for instance, or a product. It is about certain bills I have every month, and the potential to save up enough to, for instance, take a month's sabbatical where I do -not- have to work because I've got money to pay for those bills.

I suppose one could extend that idea into retirement. Money is time because I have debts to pay (or food to buy, or whatever) and those debts do not change altogether much, month-over-month. So if I make more money, I may at some point take a vacation and not earn money, thus gaining time I would otehrwise spend in the office.