FeedWind - FeedWind is the world's leading RSS widget, Facebook widget and Google Calendar widget - works on any website and is fully customizable
Free Twitter RSS Feed Generator - Convert Twitter lists, hashtags & searches into RSS feeds
Feedly - The content you need to accelerate your research, marketing, and sales.
RSS API - Convert & subscribe to RSS, ATOM and JSON-Feeds via API ⚡️ Get webhooks whenever there is a new entry in a Feed.
Superfeedr - Real-time feed API - RSS and Atom over PubSubHubbub and XMPP. Superfeedr pushes RSS feeds in real-time for both publishers and subscribers, with open protocols and APIs.
Feedbutler - Subscribe to your RSS feeds directly via email!