I have mentioned this before, but I seem far slower at noticing errors than in the past. As an example I used the Roman phrase caveat emptor on one of my blogs yesterday. Only a day later when this appeared on AmateurRadio.com did I notice that I had the wrong spelling caveat emtor. On my amateur radio blog I have corrected the mistake, but I had not seen it!
Sometimes it is a keying error, but I should have noticed this. The error has also been corrected on the Amateur Radio.com site.