AllTop is one of my favorite websites. It is a great place to find fun blogs and get your hands on more powerful content on a daily basis. While AllTop allows you to create your own personal page, many prefer to clone it on their own domain (using an AllTop style theme). There are not many decent RSS aggregator WordPress themes around, but these 3 themes should give you some options:
OneNews: OneNews is another clean premium WordPress aggregator theme. Supports all types of content and is very easy to customize. Gives your visitors the chance to change its look and the font size too (review).
Please feel free to add your suggestions below.