Yahoo pipes

This is a nice concept and tool that allows you, fairly simply, to define exactly which items from a blog feed you really want to see.So, if you like Lifehacker but have no interest in the non-computer stuff, pipes can help you.
There's a video tutorial to get you started, but it's not at all difficult, particularly if you have a scientific/engineering background.
I tried it for the first time today and set up a RSS feed which selects just things I like (Linux, Mac mostly) from Lifehacker, del.icio.us and Digg. You can see this in the right-hand sidebar at the bottom.
Impressive.
However, complained when I tried to use it in Opera so I changed to Firefox. However, later attempts seemed to be working fine in Opera 9.51