So I don't know if this fits in "funny" or elsewhere, but a thing that's been driving me nuts is misspelling of words on the internet. Specifically, people who type a word that sounds like the one they want but the one they really want is spelled differently. (Homophones, right? It's not a word I use much myself, so I had to look it up to remember it.)
For example, a friend of mine wrote "site" when he meant "cite" in a blog post recently. (He corrected it after I told him.)
But the most recent that stopped me short was somebody posting that her baby was born by c-section because of "D-cells". Even though I don't want to laugh at her situation, the spelling she used made me laugh out loud. D-cell sounds like a battery to me.
The spelling shortcut she was looking for here was "decels", as in deceleration of the baby's heart rate.
I've seen lots of other examples of this sort of thing, but those are the ones I can remember right now.