As Jeff mentioned [in his post:][1]

> There is a default tag filter on http://stackexchange.com/ but you
> must be logged in:
> 
> 1. Click on Filtered Questions
> 
> 2. Click on "Favourite tags 
> 
> Then look for the default "Favorite Tags" filter.
> 
> 
> ![enter image description here][3]
> 
> You can browse it in your browser, or have it emailed to you, or get
> the RSS feed at the bottom of the page (also present in the headers,
> too, if your browser auto-detects).
> 
> ![favorite tags RSS feed][4]


  [3]: https://i.sstatic.net/7ZRjd.png
  [4]: https://i.sstatic.net/SmbAL.png