I got a raise at work yesterday of $1/hr and they're making it retroactive to June 17, which was my one year anniversary.

When I was hired, I thought that I'd been told you got an increase after a year, but no one brought it up, so I finally got around to emailing the coordinator yesterday. She looked into it very quickly and was very apologetic that they'd missed my anniversary, and I'll get the retroactive pay as a lump sum on my next pay check, which will be a nice little added bonus.
Just shows the importance of knowing what you're entitled to and asking for it.