Yeah, true. I still have some of my half-assed ventures on the web. I keep them around though because they have taught me what works and what doesn't. Should probably just pull the plug on them though. But nostalgia says no. lol.
Were you searching for an example of an affiliate site done right? Well, it is hard to know how well they actually do without their conversion rates handy. You can have a site that looks wonderful, but converts terrible. I have done well on the product domains, others focus on services like dating. Like enlytend says, stick to something you are interested in and therefore you will be more motivated to create content and update the site on a regular basis.
Money isn't necessarily the main motivator for everyone. You need to be interested in your topic of choice to make it work. Either that or outsource your content, which does work for some. Check services like oDesk if you are interested in that.