What I did this weekend (the internet is both a blessing and a curse)

Barry Schwartz on the paradox of choice (ted.com).

Here is some comparison shopping I'm doing. These scatter plots are based on listings on cars.com, ebay, autotrader.com, carsdirect.com and vehix.com listings of the cars between 0 and $8000 dollars:

Update:

Another metric for comparison shopping.

I think this counts as the interaction effect: