Yes, I know, vinegar can't be used for every cleaning purpose, but I'd have to say it's effective for most cleaning purposes. If you're trying to disinfect your house during a flu epidemic, you should not use vinegar; it's not effective at killing viruses. However, if you're trying to get rid of mold or bacteria, use vinegar, not harsh chemicals! In an article from CBS News (from a 2009 48 Hours special), the microbiologist for Good Housekeeping magazine put vinegar to the test: the results of this particular test show that vinegar is about 90-percent effective at killing mold and 99.9-percent effective at killing bacteria. I'd say those are some pretty promising results!
I have recently used straight vinegar to clean two things that no other commercial cleaner (besides bleach) could tackle - hard water deposits on my shower head, and those gross rings around the back of the bathroom and kitchen faucets. For the shower head, I simply tied a bag of vinegar mixed with baking soda onto it and left it there for a few hours. Then I wiped it off and it was good as new! For the rings around the faucets, I soaked a few paper towels in vinegar and placed them around the faucets. I left those on for about an hour and the grime wiped off cleanly with no elbow grease at all. (Better instructions for both of these tricks can be found here.) I was extremely pleased with the results of both experiments.
I regularly use vinegar to deodorize the house (just place a bowl half-filled with straight vinegar in the room you'd like to deodorize) and as a general cleaning spray that I mostly use in the bathroom. (I fill an empty spray bottle with straight vinegar and add a few drops of tea tree oil essential oil.) Not only does this cost me less than buying several bottles of commercial deodorizers and cleaning agents, but it also spares my lungs from inhaling any harsh chemicals. Vinegar is a welcome addition to my detoxed cabinet.