Kate's general description fits me as well. The way I look at it, the more money I save by being thrifty on the things that aren't a big deal to me, the more I have to blow on the things that are.

Thrifty: Always bring my lunch from home instead of going out; drive cars until they die (my current Honda Accord will turn 16 this fall, and there's no end in sight!); ride my bike to work whenever possible; buy nonperishable groceries online (Amazon) when possible (and when shipping is free).

Spendthrift: Ride a bike (not my commuter bike) that's worth more than my car; splurge on nicer hotels (like the club room at the Mandarin Oriental in Singapore^); don't think twice about $3 or $4 coffee, as long as it's good.