You could promote affiliate products and earn up to $100.00 or more per sale.
If you sold just 5 products per day through affiliate ads and your commission was $100.00 per sale then you would earn $500.00 per day.
Some web hosting companies will also pay you $100.00 per sale through an affiliate program so if you had 5 people sign up for web hosting account you would make $500.00 per day doing that.