how do you make extra money?

i was telling jen today about my frustration with not knowing how to go about making extra money beside what's a part of my regular paycheck. that money is spoken for (bills, food, etc.) but there are things that i'd like that don't fit into any of our budgetary categories (musical gear, computer upgrades, big gifts, etc). so, you career folks, you family folks, what do you do for those special purchases? what creative options have you found?