For word lovers like myself, the Atlantic Magazine runs a column called "Word Fugitives" by Barbara Wallraff. The July/August column included responses to a woman's request for a word to describe her husband's " uncanny ability to to ask if I need help with a household task at the exact moment that I am finishing it." Of the many words that readers suggested, the one that was judged to be the "most precise and economical" expression for this ability of the woman's husbands was, not surprisingly, a portmanteau word.
afterthoughtful (afterthought + thoughtful)
What a sensational word. The next time my husband offers to help with something after the fact I will be sure to thank him for his afterthoughtfulness.