Email Based Aggregators

Following services allow you to read RSS feeds in your email client. They aggregate the feeds and send them on to you as emails.
rss2email is a simple Python script that lets you subscribe to a list of XML newsfeeds and get new items sent to you by email.

Blog Alert will send you daily email notifications when there are new posts to your favorite blog or RSS feed. No account is required.

Feed2Imap is an RSS/Atom feed aggregator. After Downloading feeds (over HTTP or HTTPS), it uploads them to a specified folder of an IMAP mail server. The user can then access the feeds using Mutt, Evolution, Mozilla Thunderbird or even a webmail.

FeedBlitz is a service that monitors blogs, RSS feeds and Web URLs to provide greater reach for feed publishers.

Queoo: Subscribe to a blog or web site with an RSS-feed and get notified when it is updated. You decide when and where to get notified – Queoo sends you e-mails or instant messages on a schedule of your choice. It's free!

RssFwd can deliver updates from RSS/Atom feeds straight into your mailbox. Excellent service!

R-Mail: A popular RSS to email gateway

Squeet Reader is the best of RSS combined with the best of Email. The result is the smartest , most efficient way to read, subscribe to, and manage your syndicated news feeds. There's no software to install, minimal use of bandwidth, and full privacy. Fully free!

Yahoo! Alerts: RSS alerts delivered via email, IM, and SMS.