Once I started really looking at this, I was utterly amazed at how it affects every aspect of our interaction with computers. And how it has become, in essence, more noise to be ignored than useful.
Spell-Check / Autocorrect — Everywhere, everyday. Occasionally useful in word processing, less useful and more annoying in GMail, genuinely distracting and painful in SMS and mobile mail.
GoogleAds and other auto-generated Ad services – I use AdBlock+ for Firefox. Once I turned it off, it was, surprisingly, not so overhwelming as I expected. I think I’ve generated an internal filter to this stuff. As long as the ads are not either (1) offensive/pornographic, or (2) those insane popups that still show up on some high end sites, I can’t really see them. They’re just more noise. That said, I use the “readability” plug-in, or Instapaper to help cut down serious infringements on reading stuff that matters.
Amazon recommendations — I buy a lot of books. Amazon is consistently one of the most useless recommendation systems out there. I’ve also tried, in no particular order: www.librarything.com, BookArmy, WhichBook, BookLamp, and What Should I Read Next?, www.goodreads.com, and www.bookseer.com. They all want me to read Harry Potter. I don’t have anything personally against Harry, but it’s not my cup of tea.
Finally, there’s LinkedIn’s and FaceBook’s “you may know” recommendations. It’s rare that I actually do know any of those people. Much rarer still that I would want to link to them.
I realize now that these suggestion services are, for the most part, something of a cross between a dynamic “filler” and mass-marketing / spam. That is, once upon a time, sites used to regularly restructure their layout with the same content so that when people came back to the site it looked new. Thankfully, people don’t do that anymore. And mass-marketing / spam has really a tiny tiny percentage of successful hits. But it’s so cheap, it’s worth it to the websites and vendors to continuously bombard us with this noise. And I’ve seen no evidence that any of the recommendation services have improved significantly over the last 10 years, so, for me, it’s simply another form of graphic noise to ignore.