If you use Google Hangouts, there's a good chance that you've accidentally said something wildly inappropriate to the wrong person when you meant to message someone else.
For example, last week I was trying to tell my fiancée what I wanted for Christmas. Moments later, I realized I had sent those messages -- which were about a Batman statue -- to a colleague who I certainly do not know well enough to be demanding comic book merchandise of. It was humiliating.
The reason for the mistake: I wasn't paying attention to what I was doing. But Google doesn't exactly help, either. Every Gchat message box looks the same. Because I was talking to my fiancée on my personal account and my colleague on my professional account, both message boxes were even on the same part of the screen.
There's a neat little trick to circumvent the problem, though. If you type "/bikeshed" into your Google Hangouts window and send the message, it'll change the color of your message box.
Pretty exciting, right? Since the, uh, incident last week, I've taken to changing the color of my fiancée's chat window but leaving everyone else's blank so that she always stands out in my inbox, ready to receive totally asinine demands for Batman toys.
If you want to reset your window back to the default color, just close and reopen it. Also, the trick is desktop-only -- though if you're using the mobile app, your chat windows will take up the whole screen, which probably cuts down on the confusion.
We first discovered the "/bikeshed" trick last year, but it hadn't occurred to me to use it like this until now. Check out our list of Google Hangout hacks for more.