start.io - a minimal web-based RSS aggregator. Easily customizable.
Safari Extensions - a new feature with Safari 5. Empower your browser. Instillation instructions here.
zootol.com - a sort of delicious.com for images. Gorgeous UI that allows for easy posting across social networks.
Cloudapp - a menu bar app that allows users to store web pages for later cloud-based reading. Excellent as a way station for later consideration.