Global Rich List
Crooked Timber sent me to this one (read the post). The test doesn't actually measure wealth, it instead ranks yearly income on a worldwide scale. $40K a year puts one in the top 4%. Americans who consider themselves 'upper middle class' will be ranked as fabulously wealthy beyond all reason.
If one were to extend the range to include all Homo sapiens sapiens throughout time the scale would probably shift another order of magnitude.
Which reminds me of this scale.
Once you take the survey you're invited to donate to CARE -- my favorite charity. They're the only charity I've ever worked with that has been able to leave me completely and totally alone. When I started donating I wrote that I'd continue with my yearly donations as long as they never called, emailed, or otherwise pestered me or even shared my address. With one trivial exception (forgiven), they never have.
I don't think any other charity could manage that. Highly recommended.