A few weeks ago I learned how to borrow money Interest Free from my bank because of how their system works. I also took advantage of that system and another slow system to prolong the interest free period.
First, the bank that I use allows checks to be scanned in from home and deposited into an account. Typically this isn't really that big of a deal, but my bank allows that money to be used instantly, up to $5000 in deposits can be made per day at my bank from home.