If we are the result of intelligent design, then why have we got a stupid appendix that we don't need? That's not intelligent... in fact it looks rather like a random flaw that is more likely the result of evolution.
As BluePriest pointed out, the appendix is actually useful. Of course, it is more likely that it is an evolutionary adaptation for an organ that we evolved not to need than that it was created to serve a purpose that could easily be done by a smaller organ that would take less energy to maintain and wouldn't be prone to inflammation that can cause death.
A quote by David Attenborough on intelligent design:
I tell them they ought occasionally to think less of beautiful things like hummingbirds and orchids and sunflowers and think of other, less attractive things. They might, for example, think of the parasitic worms that live only in the eyeballs of human beings. Think of that worm boring its way through the eye of a boy sitting on the bank of a river in West Africa. A worm that’s going to make him blind. Are you telling me that God or an intelligent designer created this worm that can live in no other way than in an innocent child’s eyeball?
Now the stock creationist response is that it used to have more functions and it "lost" them (specialisation in evolutionary terminology). This conveniently explains other deficiencies of creation, like the female human's hips being too close together to accommodate a baby (so they need to be forced apart, sometimes tearing the muscles and tendons in that region, and occasionally causing a vesicovaginal fistula - which is when the flesh between the vagina and the bladder is ripped apart, causing it to leak out the opening, which in turn causes infection and death) - when pushed apart for birth, the hips are then too far apart to walk. Actually, pregnancy has dozens of horrible design 'features'. The enlarged uterus presses on the bladder, causing incontinence (and a caesarian section does not circumvent this problem unless done prematurely). If humans had quadrupedal ancestors, then gravity would cause the foetus to avoid squeezing any important organs. Presumably when god created humans, he held the diagram the wrong way up.
Then there's ovulation, which for some women is excruciatingly painful for up to 8 days in a month. Nausea, cramps, hormonal fluctuations; some women get it all. Men aren't much better off; we have external testes that cause great pain when jolted or twisted, a prostate that in later years (after reproductive age, so not evolutionarily selected against) becomes highly prone to cancer (1 in 11 over a lifetime - not as bad as the 20% of women who experience Mittelschmerz, or painful ovulation) and swells - making urination difficult or painful. Our hearts (more on average than women's) build up lipid (fat) deposits which the body tries to "plaster over", and eventually the 'plaster' fails and a huge clot blocks off an artery and causes a heart attack (once again, evolutionarily not selected for, as it mainly occurs in people after the age of reproduction in our ancestors - 12-25). The same thing happens in the brain and causes stroke. Sometimes the pancreas doesn't produce the right amount of insulin, or the body develops a resistance to it, causing diabetes. We breathe, eat and drink through the same aperture, with the oesophagus and larynx being right next to each other.
Bile constantly forms in the liver and is stored in the gall bladder, which can form stones which are extremely painful to pass. A woman who has both passed gall stones and children could probably tell us which is worse, but it strikes me (who has experienced neither) as about equal. The sinuses get infected because they can't drain properly in a bipedal stance (another throwback to our quadrupedal ancestry). Humans can't digest cellulose, so we get very little nutrition from some vegetables and none at all from grass or cardboard
, both of which would make survival much easier (the vegetables and the grass, not the cardboard). Wisdom teeth are too large or our jaws are too small, take your pick, causing pain. Walking upright stresses the lumbar vertebrae and causes back problems in older people.
(many of these problems were taken from ScienceBlogs.com (http://"
http://scienceblogs.com/denialism/2007/11/ask_a_scienceblogger_which_par.php"), which ends with the additional observation that we can't regrow limbs like salamanders can, which sucks)