Well, according to this site (http://www.yourdictionary.com/library/misspelled.html), the hundred most commonly misspelled words are:
acceptable, accidentally, accommodate, acquire, acquit, a lot, amateur, apparent, argument, atheist, believe, bellwether, calendar, category, cemetery, changeable, collectible, column, committed, conscience, conscientious, conscious, consensus, daiquiri, definite(ly), discipline, drunkenness, dumbbell, embarrass(ment), equipment, exhilarate, exceed, existence, experience, fiery, foreign, gauge, grateful, guarantee, harass, height, hierarchy, humorous, ignorance, immediate, independent, indispensable, inoculate, intelligence, its/it’s, jewelry, judgment, kernel, leisure, liaison, library, license, lightning, maintenance, maneuver, medieval, memento, millennium, miniature, minuscule, mischievous, misspell, neighbor, noticeable, occasionally, occurrence, pastime, perseverance, personnel, playwright, possession, precede, principal/principle, privilege, pronunciation, publicly, questionnaire, receive/receipt, recommend, referred, reference, relevant, restaurant, rhyme, rhythm, schedule, separate, sergeant, supersede, their/they’re/there, threshold, twelfth, tyranny, until, vacuum, weather, and weird.
I don’t know how they came up with this list, but there you go. Some of them on the list, I can recall many people getting wrong, especially judgment, its, and millennium. Of course, this is American English.
As for me, I cannot spell individual or privilege for the life of me. Both of those have about twenty alternative spellings in my auto-correct list, so they almost never appear wrong. I also have some issues with -ent versus -ant, especially since so many of them differ between my to languages, English and French, such as independence versus independence, so I can’t use my general approach of deciding which of several spellings looks more familiar.