I used an S corp. If you actually make a profit it gets taxed once as personal income (sort of). Likewise, if you take a loss it's just negative income, not a tax deduction. In a C Corp the corporation pays taxes and the owners pay additional taxes on any income given to them as dividends. So for an S Corp you do the corporate tax return, mail in the forms and enter the numbers on the income section of your 1040. For the C Corp you do the corporate tax return, send in the forms with a check to Uncle Sam, enter the numbers on your 1040 and pay taxes again.
To do it all again I would seriously consider a LLC. Depending on the state, it's probably less paperwork hassle and cost to establish the corporate entity. Also, the taxes are easier to figure out and file. I think you can do the taxes on a schedule C like a sole owner proprietorship--someone will correct me if I'm wrong.