I was offered a job position as an artist and designer of a budding website. The rest of the team consists of 4 people: a founder, and others on such things as marketing and programming. I was offered either a percentage share of the site revenue for a fixed amount of time, or a percentage share of the whole site were it to be sold (they are not willing to sell for anything under $20,000). I have never been offered a job in such a way before, and I was wondering about the percentage (for the fixed amount of time)? I was also told to keep in mind how much time and effort they would be putting into it to consider. Money is no issue; I wouldn't want to be too demanding, but I would also not like to be ripped off. Can anyone offer advice as to the percentage I should likely receive, or should I just ask for the founder's position as to what percentage he thinks I should get?