- Rampant misuse of 'ETA': the A in ETA stands for 'arrival'. Some coworkers use it when they mean 'completion', 'delivery', or 'repair'. Wikipedia alleges that it may be used "metaphorically" or that it could stand for "achieve[ment]", but this smacks of backformation and must be shunned.
- "Let's take this offline": this means either, "Let's discuss this over private email instead of boring everyone on the CC list with the details," which is stupid because the discussion will still be online, or, "Let's discuss this once the meeting we're sharing with other people is over," which is stupid because, unless the dialogue is occurring between people on a conference call, you're already offline.
Think. Use the right fucking word, every time. Only good things can happen.