Another etymology to blow. your. mind.
do, v.
From the Old English dón, from the Proto-Germanic dæ-, do-, from the Proto-Indo-European dh?-, dh?, meaning "to place, put, set, lay." In Latin, the Indo-European /dh/ sound eventually became /f/ (through the intermediate stage /?/). This yielded the Latin facere, which shows up in various forms in Modern English, like fact and -ficent.
Interestingly, it is also believed that do reflects the only surviving word in English that used reduplication to form its simple past form. That is, the stem was repeated (Proto-Germanic deda, "did"), whereas today we typically use a suffix. And even more interestingly, it is believed that this is the source of the Germanic past tense suffix. In other words, early Germanic speakers took the reduplicated -da and started using it on other verbs to mark the past tense.
And the last interesting tidbit is that do was one of the last words in English (well, in Old English, anyway) to use the -m suffix for the first person present indicative. This suffix survives in only one place: the word am.