pedestrianFirst, the whole "cars stay out of the middle of the intersection" business is clearly just for losers. When pedestrians are allowed to cross, the cars stop exactly abutting BOTH sides of the crosswalk.
Pedestrians don't usually jaywalk, but when there is absolutely no chance of getting hit by a car (especially on the Paseo de Castellana on my way to work - requires 3 crosswalk signs to cross), everyone will make a run for it to the other side.
When in Spain, know the words. The word that Spaniards use for bike is bici (pronounced bee-see), when the textbook word is bicicleta.
Those who do ride bikes seem to be strongly in favor of the folding bike - it's easy to take in the subway, store in the apartment, and feel engineer-like when assembling it out on the street. My roommate even has one - they are more common by a factor of 3:1 in terms of regular bikes.
An interesting bike lane tidbit albeit in Seville was that the bike lanes also included wheelchairs.
Seville was much more up-to-date on the whole bike lane thing, so everyone was riding a bike (although I can't imagine it being pleasant, considering it was 100+ degrees with no breeze).
As expected, the cars are smaller than cars in the US. 2-door cars are common, and I've never once seen a pickup truck (and I've been to the countryside!).
Gas prices are a bit ridiculous, though. In the States we pay by the gallon and fill up 12+ gallons to a tank. Here, they pay by the liter, use diesel fuel, and fill up a tank of ~8 gallons instead. For reference, while we think our $3.50/gallon prices are bad, try 1.50 euros/liter. Yowie.
But it seems to me that the only gas station I've seen is one right on the side of the road. That's right, you drive on the road, don't even pull into a shoulder, and BOOM, you have gas.
And to everyone who loves driving manual-transmission cars - you'll love it here. It's very hard to find a car with automatic transmission, even here in the center of the city. When we were going on the lab retreat, I couldn't even drive because I don't know how to drive stick. All my labmates were laughing at me, but in the States automatic transmission is the norm.
I bet combining diesel, smaller cars, and manual transmission makes the cars here much more fuel-efficient....