Is there any website/service which will enable me to add RSS subscription to any website?
This is for my company I work. We have a website which displays company related news. These news are supplied by an external agency and they gets updated to our database automatically. Our website picks up random/new news and displays them. We are looking at adding a "Subscribe via RSS" button to our website.
If you have the data in your database, creating one yourself is fairly straight forward - there's a simple tutorial here.
Once you've set up a feed, in the <head> of your page, you put text like:
<link rel="alternate" title="RSS Feed"
href="http://www.example.com/rss-feed/latest/" type="application/rss+xml" />
This allows the feed to be "auto-discovered" by your user's browser (e.g. the RSS icon appears in the address bar in FF).