I discovered that I tend to not think of things in terms of dollars and cents.
I tend to think of them in units of what's important to me at the time.
Pack of Magic cards: ~$3
Month of Runescape subscription: $5
Box of 36 Magic packs: ~$90
Everything else tends to get thought of in terms of these.
For example (all figures are approximate):
No-frills dinner for two at favorite place(s): 10 Magic packs or 6 months of RS
Dinner for two with alcoholic beverage and dessert: 15 Magic packs or 9 months of RS
Rent/month: 3 Magic boxes
Car payment: 1 Magic box
Fable III Collector's edition: 1 Magic box
Coffeemaker of the gods: 2 Magic boxes
Trip to Costco: arm, leg, body, soul
It's really simple when you think about it.
Does anyone else do this?