When it comes to business partnership I am always quiet cautious because of the numerous stories that we have heard and the negative experiences I have had!
Nonetheless, I would like to highlight the truth that if sharing 50% of a deal with someone will increase your profit by more than 200% then it is wise to share your profit! For example, if you have a blog that is earning $50 every month, why not find someone who is good with Internet marketing who may believe in your idea to help you increase your earnings to $1000 every month and you share the monthly increase with him or her for a specified number of months or based on ongoing level of support!
Look out for people who can work with you to achieve a greater result and find ways to work with them. In any case always make sure terms are clearly written and signed!