Take on a second job. It's not glamorous or particularly creative. However, the reality is that you need money to make money. Save as much as you can for start-up or investment capital. Be aware that having two jobs will reduce the amount of time and energy you can devote to classes.
Buy a house. Most students either live in the dorms or rent while they are in college. This is just money down the drain. Purchase an inexpensive house with several bedrooms so that you can rent it out to roommates. Using a first time home-buyers' loan might significantly reduce, if not eliminate, your down payment. If this is not possible, you may be able to afford a house by getting together with several friends and having your parents co-sign on a mortgage. If you play your cards right, you will not pay much more each month than you would as a renter. If you are particularly creative, you could manage it so that your roommates basically pay the mortgage for you. When you graduate, you can keep the house to live in, rent it out as an investment property or sell it.
Start a business that has a low overhead. For example, if you are a talented programmer, you can run a website with only limited costs and potentially make a great deal of money off of the ad revenue. Other possibilities include an in-dorm movie rental business, photographing weddings or playing musical gigs. If your business requires a great deal of start-up capital, you may want to look into a business loan. It is difficult to predict how much the business will make, especially since you will be limited by the time constraints that class and homework place on you. However, every bit of money you earn will help and so will the experience of starting and managing your own business.
Play the stock market. If you have savings and understand market fundamentals, stock market investing might be a way to get rich quickly. However, it is also the riskiest since a bad investment could wipe out your savings.
Buy lottery tickets. Seriously. Your chances of actually succeeding in a get rich quick scheme are probably about the same as winning the lottery. As a bonus, you can buy a lottery ticket quickly and inexpensively.
Live frugally. People want to become rich so that they can have comfortable, lavish lifestyles. However, before you become a millionaire, you need to put every bit of spare change that you have into a savings account or money market account to earn interest.
Avoid accumulating debt. If you can live without a credit card, you should. Take out as little in student loans as possible. Live within your means. The less debt you have, the fewer constraints there will be on your financial achievements.