Usually involves using pubic instead of public. But I decline to use in a full sentence.

Yeah, the funniest-saddest example I can think of is a real-life example I described here:

Some time ago, an instructor of mine, with a newly conferred Ph.D., offered me the chance to read his thesis. "Wait until it's bound," he said, "it'll be easier to handle."

It was an examination of the perception of public safety in [particular field]. On the bottom of the very first page, he had typed the phrase "pubic safety." Another typo I found in the first couple of pages: "pubic perception of risk."

These typos appeared sporadically through the entire text. Evidently, he never thought to do a search-and-replace substituting "public" for any stray occurences of "pubic."

I sent an email to my ex recently, discussing how my oldest and I would pass some time, while my youngest was at a birthday party...I sent this:

"I'd figured I'd take her out there early and go to Top Notch Toys on the way, and then kill tim with Sophie."

I then sent a follow up indicating that Tim had nothing to fear, really, that we'd leave him alone.

Here's one from an email that was sent to me today, in reply to my asking whether my correspondent had seen Boardwalk Empire yet:

Not yet. I love Buscemi in, well, every last thing, so I’m looking forward to it. the opportunity hasn’t arisen – I am pretty sure that I don’t have a channel that carries it as I don’t have a huge cable package (almost just said “huge package” there then realized you’d goof me on it to no end), and it’s not on Netlix.

I thought it was an especially funny typo given the care he took not to give me an opportunity to rib him about not having a huge package, and I asked him if "Netlix" was some kind of interactive p0rn site.

Won't get full credit here, but my OCR scanned "embouchure" as "oink-touchup".

and then kill tim with Sophie.

Ah, yes—one of Quentin Tarantino's lesser known works.

Bahaha...yes. The good thing is that I'm pretty sure Sophie would have talked me out of it anyway. She's good like that.

I once had a letter where someone wanted not a 'gesture of goodwill' but a 'Jester of Goodwill'.

"I've had to overcome a lot of diversity".

Cleveland Cavaliers player Drew Gooden on the ups and downs of his NBA career.

A twofer: A long time ago, I found on a workplace bulletin board a directive that the shop floor would be "swepted and moped" on a weekly basis.

Doing freight, I used to label orders "ship to arrive by [date]". The freight company would take my notes and put them into their system. I once got a bill that said "Shit to arrive by [date]". My manager said I should call them to see if the shit got there on time. At the same company, we once received a box of fliers that contained "1000 shits" instead of "1000 sheets".

This week, our collections guy told someone that someone's statement would be corrected when the amended rats took place. Not rates, but rats.

I'm always typing suxty instead of sixty.

I once finished a note on a door white board with "Your pen is." Unfortunately, due to space constraints, I was writing with very tight kerning.