What are some ways to make extra money while in college?

I want to know some cool ways to make some extra cash while in college. Getting a job is the easy answer, and nothing illegal is an option, but I want to know some ideas on how to make extra cash.

you have to get in touch with a person who does these focus groups- they are great. you get food and drink while you are there and usually $100 to $300 for an hour or an hour and a half of answering dumb questions. the trick is to be able to print out business cards so u can pretend to be whatever sort of person they need. here is another great trick- they always overbook in case people don’t show up- so u want to arrive promptly at the time that it begins. If they already have enuf people and you are there on time- you get paid and you go right home.