In a lot of ways, I'm considered smart. I have a Ph.D. in organometallic chemistry, brain teasers are my idea of fun, and I'm currently reading the Decameron just because I've never read it. In a lot of other ways, I am (to put it politely) dumber than a dust-bunny. About once a week, I lose important things (keys, wallet, phone). I recently poked myself in the eye with a knitting needle while trying to make a scarf. I've been known to pass out simply because I forgot to eat for several days.
So I definitely understand the idea that intelligence is hard to define and incredibly hard to quantify. I view IQ tests suspiciously, and I don't find them helpful in terms of helping me understand how I think, or how most people think.
However, that was before I saw the UK Medical Research Council's Ultimate Intelligence Test. These prominent neuroscientists have identified 12 "Pillars of Wisdom" (including visiospatial memory, planning, verbal reasoning, etc). They are analyzing all sorts of things; how these different kinds of thinking fit together, how test performance relates to brain activity (functional MRI), the correlation between smoking or being left-handed and test performance, etc.
The tests are simple (like True/False: the circle is bigger than the square) but much more challenging than most versions I've seen. Many are free, and if you register you can take part in the study. This is much more useful than most "Learning Styles inventories" I've used. It provides actual measures of what you're best at, which can be really useful when thinking about how you learn. Go play with them here.