You can easily offload your feeds to an a external service like Feedburner. But what if you want to serve feeds for categories, tags, authors and single posts, just like WordPress by default does? This article explains how I moved all feeds to feed.webmasterview.com. This is not offloading, feeds are still in the same server, but this helps you to have separate web logs for feeds and keep your main apache access log uncluttered with feed requests.